Key Exercises and Training for Aging Successfully and Living Your Best Life

As the years have rolled by, nothing has become more clear to me with each passing day than the fact that aging successfully requires a lot of work. When it comes to our bodies, nothing rings truer than “If you don’t use it, you lose it.” This is particularly true when it comes to preventing declines arising from disuse, but also when trying to slow down the normal impacts of aging.

The function of our bodily systems peaks at around age 25 and declines over time. As a result, your maximal aerobic capacity decreases over time, even with constant training, reflective of declines in maximal heart rate. What’s more, your balance ability gets worse (particularly after age 40), bones get thinner, muscles atrophy, reflexes get slower, and recovery from workouts takes longer. Aging is not for sissies (but it beats the alternative)!

The good news is that is it possible to at least slow how rapidly most of these systems decline by changing how you live your life. By including regular physical training, better nutrition, adequate sleep, and stress management, you can delay or prevent a lot of normal aging and reverse decrements caused by inactivity, neglect, disuse, and abuse of our bodies. (The only one we really can’t slow or reverse is our neurological decline.)

It starts to seem like preventing additional declines from inactivity or inadequate training gets to be a full-time job as you get older, and you have to keep adding in additional exercises, stretches, and activities. A fitness instructor recently confirmed that it’s a bit like playing whack-a-mole: fix one weak area or physical problem and another one pops up. Welcome to aging!

So what can you do to live your best life, physically and mentally? I would suggest adding at least these (and many other) critical exercises to your weekly routine:

Cardiorespiratory fitness: Cardio workouts with faster training intervals

In addition to doing regular cardio activities like walking, cycling, and swimming, add in some faster intervals into any workout, such as walking faster for 10 to 60 seconds at a time during your normal walk or doing a hill profile on a cardio training machine. Doing so will increase your fitness more and improve insulin sensitivity for longer. It’s also fine to do high-intensity interval training (HIIT) at least once a week, but start out slowly and progress slowly to prevent injuries and demotivation. Not all your workouts should be equally intense, and varying your aerobic activities also lowers the risk of getting injured.

Muscular strength and endurance: Resistance training exercises

It is easy to work on your muscle strength and muscle endurance by doing a series of resistance exercises targeting your major muscle groups (in the upper body, lower body, and core areas). Pick at least 8 to 10 exercises that cover all these areas and do them at least two to three days per week. It’s fine to use your own body weight, household items (like full water bottles), hand weights, or resistance bands as resistance—you don’t have to have access to a gym or leave home. Adding in these exercises to your weekly routine is critical to aging well and being able to live independently throughout your entire lifespan.

Balance ability: Standing on one leg at a time (and other balance exercises)

This simple exercise involves standing on one leg for a minute, switching to the other leg, and repeating. Have something you can grab onto nearby, such as the back of a chair. You can hold on with both hands, one hand, one finger, or nothing as you get better at balancing. To challenge yourself, move your free leg in different directions (e.g., out front, to the side, behind you) while standing on the other one, or practice standing on uneven surfaces, such as a cushion. If your balance ability is really getting to be an issue, include other balance training activities each week as well.

Joint mobility and cartilage health: Stretches for all your joints

Do a series of flexibility exercises that stretch your joints in all their normal directions to maintain and increase their range of motion. With aging, we are all losing flexibility and diabetes can accelerate this loss when extra glucose sticks to joint surfaces (cartilage) over time and makes them more brittle. Try to stretch at least two to three days per week. The older you get, the longer you should hold each stretch (up to a minute on each one), and you may need to add in specialized stretches (such as for your calves or hips) to really work tighter joints to enhance your mobility and balance ability.

Bone strength: Weight-bearing activities and/or resistance training exercises

Your bones stay stronger when you put normal stress on them regularly, such as carrying your own body weight around when walking or jogging or doing resistance exercises with your upper body or carrying grocery bags. If you stay sedentary, your bones will lose minerals faster and get thinned out more quickly, and non-weight-bearing activities like swimming and cycling just don’t have the ability to build bone as much as weight-bearing ones. Try to adequately stress your bones to stimulate the bone mineral density to stay higher—at least two to three days per week.

Basic mobility and self-care: Wall sits and/or sit-to-stand exercise

Until you start to get older, you seldom think about how difficult it can be to get up out of a chair or off the sofa. Many older people get heavier and weaker and start to have trouble doing these basic maneuvers, which are critical to living well independently. To improve your ability, practice doing wall sits, which involves sitting against a wall with your hips and knees at 90 degree angles and your feet straight below your knees for as long as you can. This exercise will also help prevent knee pain and problems. Alternatively, you can do sit-to-stand exercises where you sit on the edge of an armless chair and practice getting up without using your arms. (This is also often called the “getting up from the toilet” exercise.)

Sexual enjoyment (and incontinence): Kegel exercises

Also known as pelvic floor muscle training, Kegel exercises can help with stress incontinence (i.e., urinating a little when sneezing or laughing) and normal incontinence (both urinary or fecal), and they may enhance your sexual pleasure to boot. The easiest way to identify the pelvic floor muscles is to stop your urine flow while urinating or tighten the muscles that keep you from passing gas. To do Kegels, imagine you are sitting on a marble and pretend you’re lifting it up by tightening your pelvic muscles and holding them contracted for as long as you can; do this a few times in a row. When your muscles get stronger, you can do these exercises while sitting, standing, or walking. Both men and women can and should do Kegel exercises regularly.

A Potential New Oral Medication for Type 1 Diabetes and How It May Affect Exercise

Have you heard of TTP399? Despite its completely forgettable name used in clinical trials, this potential new oral medication may have the power to lower and stabilize blood glucose in people with type 1 diabetes (T1D). If approved, TTP399 (which would be given a spiffy new brand name) will be the first oral pill to treat T1D. You’ll still need insulin, but TTP399 should lower blood glucose without raising the risk of diabetic ketoacidosis (DKA), and it won’t increase the risk for low blood glucose either.

So, how does this new drug work and why should you get excited about it? TTP399 works on your liver to activate an enzyme called glucokinase. You may be wondering, what is glucokinase and why does it need to be activated? And why isn’t it already activated in people with T1D?

I actually know a thing or two about glucokinase given that my PhD work was in glucose and fatty acid turnover during exercise. As you may know, the liver plays a central role in maintaining a normal blood glucose level, which it accomplishes by storing or releasing glucose depending on your blood glucose levels and activities—assuming everything works well with insulin and glucagon release by the pancreas.

Normally, the beta cells of the pancreas make insulin while the alpha cells make glucagon. What happens in T1D is that insulin release from the pancreas is insufficient or absent altogether, and the usual balance of insulin and glucagon—with insulin rising after meals and glucagon rising during fasting and exercise—that signals the liver what to do to keep your blood glucose normal is lost. Even when you replace insulin through injections, pumping, or inhalation, it never reaches as high of levels as normal in the liver circulation, causing a “sleeping liver” with key metabolic enzymes never being activated. The result: Both a lesser storage of glycogen in the liver and an excess release of glucose after meals and overnight due to glucagon being unchecked by insulin.

This is why glucokinase activation is so important. Activated glucokinase stimulates glucose uptake from the blood and synthesis and storage of glucose in the liver as glycogen (1,2). Having it normally activated would make you need less insulin on a daily basis because your liver would take up and store blood glucose after meals like it is supposed to.

In the pancreas, activated glucokinase acts as a glucose sensor in the beta cells, allowing rising glucose levels to stimulate insulin secretion when glucokinase is activated in people with T2D or anyone with T1D with any insulin-making capacity left (3). In the alpha cells, glucagon secretion is normally triggered by hypoglycemia and suppressed by high glucose levels, but impaired suppression of glucagon is a hallmark of diabetes—in T1D due to insulin deficiency and in T2D due to insulin resistance and/or deficiency (4). Glucose sensing in the alpha cells can limit the release of glucagon but—you guessed it—that also requires activated glucokinase (4). When inactive, too much glucagon gets released and raises your blood glucose—even after meals when your levels are already higher.

How does this all impact exercise? If your liver has been stimulated by activated glucokinase to store more glycogen pre-exercise, you should have more to release to keep your blood glucose from dropping when you are active (since glucagon rises during physical activity), and you would be less likely to experience lows during and even following exercise. Sufficiently activated glucokinase in your pancreatic alpha cells should also reduce those pesky glucose elevations frequently experienced in the early morning hours by many people.

You really do want your glucokinase activation to be back up to normal in your liver and your pancreas, and TTP399 may just prove to be the way to do that in people with T1D. In the SimpliciT1 study (5), use of TTP399 resulted in both a decrease in A1C and in the amount of insulin that participants needed over 12 weeks, including 11 percent less insulin for meals, as well as two more hours a day with their glucose levels in an optimal range. Apparently, even with less insulin on board and a lower risk for hypoglycemia, people were not more likely to develop DKA, thus avoiding the major pitfall of medications like SGLT-2 inhibitors that have been used off-label (that is, without FDA approval) by some with T1D that can lead to DKA even with normal blood glucose levels.

TTP399 was recently given breakthrough therapy designation by the U.S. FDA. This designation provides the developer with added support and the potential to expedite development and review timelines for a promising new medicine. Let’s hope that the final trials being done on this medication prove it to be as effective as the earlier ones.

References:

  1. Adeva-Andany MM, González-Lucán M, Donapetry-García C, Fernández-Fernández C, Ameneiros-Rodríguez E. Glycogen metabolism in humans. BBA Clin. 2016 Feb 27;5:85-100.
  2. Matschinsky FM, Wilson DF. The Central Role of Glucokinase in Glucose Homeostasis: A Perspective 50 Years After Demonstrating the Presence of the Enzyme in Islets of Langerhans. Front Physiol. 2019 Mar 6;10:148.
  3. Toulis KA, Nirantharakumar K, Pourzitaki C, Barnett AH, Tahrani AA. Glucokinase Activators for Type 2 Diabetes: Challenges and Future Developments. Drugs. 2020 Apr;80(5):467-475.
  4. Basco, D., Zhang, Q., Salehi, A., Tarasov, A., Dolci, W., Herrera, P., et al. (2018). α-cell glucokinase suppresses glucose-regulated glucagon secretion. Nat. Commun. 9, 1–9.
  5. Klein KR, Freeman JLR, Dunn I, Dvergsten C, Kirkman MS, Buse JB, Valcarce C; SimpliciT1 research group. The SimpliciT1 Study: A Randomized, Double-Blind, Placebo-Controlled Phase 1b/2 Adaptive Study of TTP399, a Hepatoselective Glucokinase Activator, for Adjunctive Treatment of Type 1 Diabetes. Diabetes Care. 2021 Apr;44(4):960-968.

Sheri R. Colberg, PhD, is the author of The Athlete’s Guide to Diabetes: Expert Advice for 165 Sports and Activities (the newest edition of Diabetic Athlete’s Handbook). She is also the author of Diabetes & Keeping Fit for Dummies, co-published by Wiley and the ADA. A professor emerita of exercise science from Old Dominion University and an internationally recognized diabetes motion expert, she is the author of 12 books, 34 book chapters, and over 420 articles. She was honored with the 2016 American Diabetes Association Outstanding Educator in Diabetes Award. Contact her via her websites (SheriColberg.com and DiabetesMotion.com).

How to Address Those Nagging Joint Injuries and Pain

Back in late 2017, one of my columns addressed whether you can determine if your joint issues are related to being active, normal aging, or diabetes (SheriColberg.wordpress.com). The answer was that you really can’t determine the exact cause(s), but any or all of them may be contributors. Does it matter more if you know the underlying cause if you can figure out the best treatment? Let’s discuss this more in the context of my own recent injuries.

Over the past three years, I have continued to have nagging joint injuries or develop new ones, all while being as physically active as possible (and still aging and having type 1 diabetes). For example, I had an acute painful issue with the plantar fascia (arch) of my left foot after walking (with shoes on) on the beach for miles, which forced me to hobble around on the outer edge of that foot for weeks afterward and led to a stress fracture in my fifth metatarsal (outer foot bone) that took the usual 6-8 weeks to heal. I assumed it would be fine after healing, but when I resumed my normal 5-mile walks (on pavement, not the beach), I started experiencing pain around the outer side of my left ankle and foot—which I have been dealing with off and on now for close to three years. What do you need to know about dealing with similar chronic, nagging injuries? The following points are relevant:

#1: Determine the underlying issue

Even if you do not know the cause of your problem (such as aging or diabetes), it helps to know what the underlying issue is. In my case, my ankle/foot pain was due to inflamed peroneal tendons (peroneal tendinitis), which I first self-diagnosed and then had confirmed by a podiatrist. X-rays and other tests may be able to determine if you have arthritis in joints and allow you to rule out other issues. My current finger issues recently were identified by a hand doctor as a Dupuytren’s contracture and a trigger finger, both of which I could be more prone to due to genes, injury, or diabetes (1).

#2: Find the best treatment to fix the problem instead of just treating the symptoms

I tried many different remedies on my own to deal with my ankle/foot symptoms for years, including the traditional R.I.C.E. (rest, ice, compression, elevation), occasional ibuprofen, different shoes, supports in my shoes, and walking less far or less frequently, depending on the level of pain and inflammation. None of these treatments worked long-term. More recently, I revisited my podiatrist for a referral to a physical therapist—who finally helped me fix the real problem (and it was not the ankle inflammation). I had weak muscles in my lateral foot and a severe lack of flexibility in my calves and ankles; the tendinitis was a result of the way these problems made me walk.

#3: Most treatments involve both stretching and strengthening exercises

Although I thought I was doing plenty of regular stretching to stay flexible (since all of us are losing flexibility as we age, and diabetes can accelerate these losses), fixing my chronic ankle joint pain required going beyond the normal exercises I had in my repertoire. This is where the physical therapist helped tremendously. From her I learned that I had not been stretching effectively, neither long enough nor focusing on the right areas. In older age, people likely need to hold each stretch closer to 60 seconds total rather than just 15 to 30 seconds, and I had to do stretches other than my normal ones to overcome the tightness in my calf muscles. Not being able to dorsiflex my ankle normally due to inflexibility when walking was contributing to the problem. Even just typical loss of motion around joints with aging can interfere with people doing normal daily activities, and diabetes and physical inactivity can contribute to inflexibility. Especially in older individuals, some decreasing flexibility may be related to nerve dysfunction and not just to structural changes in the muscle-tendon unit (1-3), but stretching still helps regardless.

One other important aspect of overcoming my joint issue was learning the appropriate strengthening exercises to do. I have been consistent with resistance training for most of my adult years, but when it came to my left ankle and foot, my compensatory bad walking techniques had caused me to lose the strength needed to keep my foot from rolling out. I had to learn and frequently practice many exercises targeted at restoring the strength of my foot and ankle in order to walk properly (heel to toe) and reduce my ankle tendon irritation.

Adequately strengthening the muscles in various areas of our bodies is critical to managing and preventing many joint issues and pain. Working to strengthen a weak back and core muscles can reduce and prevent low back pain; exercises strengthening muscles around affected joints can lessen arthritic pain; and even Kegel (pelvic floor) exercises can help control urinary incontinence. In the case of an issue like Dupuytren’s contracture or trigger finger, too much stretching may actually aggravate the condition, but it still helps me to keep the surrounding muscles strong with targeted finger and hand exercises.

#4: Seek out expert help for solutions (if you need to)

It took a physical therapist to set me on the right path to overcome my ankle/foot problem, even though I consider myself to be quite knowledgeable about exercise, so don’t feel bad if you need to seek out expert help in learning the right exercises to do. Just keep in mind that disuse is the greatest contributor to muscle atrophy and weakness, although being too active (and bad form) can sometimes cause problems as well. In general, it takes regular (and specific) training exercises—for both flexibility and strength—to stay on top of joint and muscle health. In most cases, it is not just aging or diabetes alone that causes your joint issues.

References:

  1. Broekstra DC, Groen H, Molenkamp S, Werker PMN, van den Heuvel ER. A Systematic Review and Meta-Analysis on the Strength and Consistency of the Associations between Dupuytren Disease and Diabetes Mellitus, Liver Disease, and Epilepsy. Plast Reconstr Surg. 2018 Mar;141(3):367e-379e.
  2. Hirata K, Yamadera R, Akagi R. Associations between Range of Motion and Tissue Stiffness in Young and Older People. Med Sci Sports Exerc. 2020 Oct;52(10):2179-2188.
  3. Nordez A, Gross R, Andrade R, Le Sant G, Freitas S, Ellis R, McNair PJ, Hug F. Non-Muscular Structures Can Limit the Maximal Joint Range of Motion during Stretching. Sports Med. 2017 Oct;47(10):1925-1929.
  4. Konrad A, Tilp M. Increased range of motion after static stretching is not due to changes in muscle and tendon structures. Clin Biomech (Bristol, Avon). 2014 Jun;29(6):636-42.

Is Weight Loss or Physical Activity More Important for Preventing Type 2 Diabetes?

Ever since the U.S. Diabetes Prevention Program (DPP) multicenter trial was completed nearly two decades ago (1), we have known that it is possible to prevent, or at least delay, prediabetes (an insulin resistant state) from progressing into full-blown type 2 diabetes. Why? Diabetes risk was reduced by 58% in the “intensive lifestyle” (ILS) participant group and by 31% in the metformin (an oral glucose-lowering medication) participants compared to no intervention (“placebo” group). For participants who were 60 years or older, lifestyle changes worked much better to prevent diabetes than taking metformin (1,2).

As an exercise physiologist, what I have always disagreed with about the DPP trial is its greater emphasis on weight loss than on physical activity. Admittedly, ILS consisted of a goal of losing 7 percent of body weight (only 14 pounds if you weight 200) by following a low-calorie, low-fat, high fiber diet and doing at least 150 minutes per week of a moderate physical activity (like brisk walking). In a follow-up report (2), for every kilogram (2.2 pounds) of weight loss, type 2 diabetes risk was reduced by 16%.

However, in the DPP, both a lower percent of calories from fat and increased physical activity predicted weight loss. Typically, it is easier for people to lose some weight than to keep it off afterwards, and that study reported that increased physical activity was critical to maintaining a lower weight. Even among the 495 participants who failed to meet the weight loss goal of 7% loss the first year, those who exercised regularly still had a 44% lower diabetes incidence (without weight loss!), and only the regular exercisers kept the weight off (2). In my mind, that means that physical activity is likely more important.

For the 10-year DPP Outcomes Study (DPPOS) and the 15-year follow-up, all original DPP participants were offered intensive lifestyle management training (3,4). During the first 7 years, diabetes incidence rates decreased by 42% in those who had not been doing ILS or taking metformin previously (DPP placebo group) and by 25% in the DPP metformin participants (who had the option to keep taking metformin); by way of comparison, those in ILS during the DPP increased diabetes rates by 31% during follow-up (5). That seems like a horrible outcome for the DPP ILS participants who only had to keep up their lifestyle changes.

On further analysis, no combination of changes in weight, physical activity, diet, smoking, and antidepressant or statin use explained the DPPOS lower rates of diabetes progression in placebo and metformin groups, but…weight gain was associated with higher rates in the ILS group. That also seems like a bad outcome. Did these participants stop exercising or become less active during the follow-up study? Statistically speaking, physical activity was not a factor that accounted for their increased diabetes rates, but in practical terms, even small changes in activity can make a big difference in blood glucose and body weight management. It’s also important to note that the ILS group still had the overall lowest rates of diabetes incidence at the 15-year mark, even though they rose closer to the other groups (4).

Although the DPP established combined lifestyle improvements (diet, activity, and weight loss) as the best way to prevent type 2 diabetes, a more recent study attempted to determine how much exercise alone contributes, along with the optimal intensity of exercise since most DPP participants did brisk walking (6). Three study groups did varying amounts and intensities of exercise while the fourth followed diet and exercise strategies like the DPP to lose 7% of body weight. Interestingly, a higher amount of moderate-intensity exercise by itself (the equivalent of walking about 13.8 miles weekly) was very effective at improving how well people responded to consuming a large amount of glucose (via an oral glucose tolerance test) despite a relatively modest 2-kilogram (4.4-pound) loss of body fat, which suggests that a higher amount of moderate-intensity walking may work as well as combined approaches for preventing the progression to type 2 diabetes. It should be noted, however, that only the diet and exercise group experienced a decrease in fasting blood glucose levels in that study (6).

So, does physical activity matter? I still maintain that it is as important as—if not more important than—losing weight when it comes to preventing diabetes and managing insulin resistance (even if you have type 1 diabetes), especially since most people have trouble keeping the weight off and only regular physical activity is guaranteed to help you do that. Importantly, the latest follow-up study coming from the DPP just confirmed that I (and others) were right all along (7). In that study, cumulative diabetes incidence remained lower in the lifestyle compared with the placebo and metformin randomized groups and this difference could not be explained by changes in body weight. Examining the self-reported physical activity overall revealed that physical activity was inversely related to diabetes, meaning that the more active people were over time, the less likely they were to develop it, regardless of their body weight. Eureka!

Losing the right type of weight matters as well (that is, mostly fat and not much muscle), so if you are dieting, make sure you include regular activity (particularly resistance exercise) to retain more of your insulin-sensitive muscle mass (8).

References:

  1. Knowler WC, Barrett-Connor E, et al. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002;346(6):393-403.
  2. Hamman RF, Wing RR, et al. Effect of weight loss with lifestyle intervention on risk of diabetes. Diabetes Care. 2006;29(9):2102-7.
  3. Diabetes Prevention Program Research Group, Knowler WC, et al. 10-year follow-up of diabetes incidence and weight loss in the Diabetes Prevention Program Outcomes Study. Lancet. 2009;374(9702):1677-86.
  4. Diabetes Prevention Program Research Group. Long-term effects of lifestyle intervention or metformin on diabetes development and microvascular complications over 15-year follow-up: the Diabetes Prevention Program Outcomes Study. Lancet Diabetes Endocrinol. 2015;3(11):866-75.
  5. Diabetes Prevention Program (DPP) Research Group, Hamman RF, et al. Factors affecting the decline in incidence of diabetes in the Diabetes Prevention Program Outcomes Study (DPPOS). Diabetes. 2015;64(3):989-98.
  6. Slentz CA, Bateman LA, et al. Effects of exercise training alone vs a combined exercise and nutritional lifestyle intervention on glucose homeostasis in prediabetic individuals: a randomised controlled trial. Diabetologia. 2016;59(10):2088-98.
  7. Kriska AM, Rockette-Wagner B, Edelstein SL, et al. The Impact of Physical Activity on the Prevention of Type 2 Diabetes: Evidence and Lessons Learned From the Diabetes Prevention Program, a Long-Standing Clinical Trial Incorporating Subjective and Objective Activity Measures. Diabetes Care. 2021;44(1):43-49.
  8. Colleluori G, Aguirre L, et al. Aerobic plus resistance exercise in obese older adults improves muscle protein synthesis and preserves myocellular quality despite weight loss. Cell Metab. 2019;30(2):261-273.e6.

Is It Possible to Train Low-Carb and Compete High-Carb?

In the past, most elite athletes attempted to improve performance through strategies to achieve “high CHO availability,” meaning building up adequate pre-exercise glycogen levels and carbohydrate intake during competition to meet fuel needs (think pasta parties the night before and high carb intake during events and competitions). More recently, many have aimed instead for a strategy called “low CHO availability” to potentially enhance the adaptive responses to training or recovery with low carbohydrate intake and storage in muscles, often achieved with periodization of carbohydrate intake (1). Periodically doing endurance training with reduced carbohydrate availability but competing without carbohydrate intake restrictions (i.e., training low-carb and competing high-carb) may promote superior metabolic training adaptations compared with a high carbohydrate intake all the time, at least in athletes without diabetes (2).  How well these strategies work for athletes with diabetes is unknown, although limiting carbohydrate intake after training has the potential to increase the incidence of nocturnal blood glucose lows in insulin users (3).

Supplementing with carbohydrate on as “as needed basis” during endurance activities may assist active individuals following a low-carb diet while training (2). Individuals with type 1 diabetes have been shown to effectively balance their blood glucose levels while supplementing with 75 grams of carbohydrate per hour of multi-day and prolonged activities, even though higher levels of insulin may be required to maintain normal blood glucose levels (4, 5). For intermittent sports like soccer, consuming 30 to 60 grams of carbohydrate per hour may prevent the fatigue or hypoglycemia that can occur toward the end of a game, at least in athletes without diabetes. Adapting to chronically low intake of carbohydrate results in higher rates of fat oxidation and use in elite ultraendurance athletes, even though their use of muscle glycogen during training is not lower and muscle glycogen repletion during and after a 3-hour run is similar to athletes with a higher carbohydrate diet (6). However, an enhanced ability to use fat as a fuel after adapting to a low-carb diet may or may not improve performance, even if performance during competitions and events is maintained. Research is lacking on such long-term adaptations and performance in athletes with diabetes, but the assumption is that if blood glucose levels are well managed, responses should be similar.

Adapted from Colberg SR, Nutrition and exercise performance in adults with type 1 diabetes. Canadian Journal of Diabetes, 44(8):750-758, 2020 (https://doi.org/10.1016/j.jcjd.2020.05.014)

References:

1.    Jeukendrup AE. Periodized Nutrition for Athletes. Sports Medicine. 2017;47(Suppl 1):51-63. doi: 10.1007/s40279-017-0694-2. PubMed PMID: 28332115.

2.   Impey SG, Hearris MA, Hammond KM, Bartlett JD, Louis J, Close GL, et al. Fuel for the Work Required: A Theoretical Framework for Carbohydrate Periodization and the Glycogen Threshold Hypothesis. Sports Medicine. 2018;48(5):1031-48. doi: 10.1007/s40279-018-0867-7. PubMed PMID: 29453741.

3.   Scott SN, Anderson L, Morton JP, Wagenmakers AJM, Riddell MC. Carbohydrate Restriction in Type 1 Diabetes: A Realistic Therapy for Improved Glycaemic Control and Athletic Performance? Nutrients. 2019;11(5):1022. doi: 10.3390/nu11051022. PubMed PMID: 31067747.

4.   Adolfsson P, Mattsson S, Jendle J. Evaluation of glucose control when a new strategy of increased carbohydrate supply is implemented during prolonged physical exercise in type 1 diabetes. Eur J Appl Physiol. 2015;115(12):2599-607. doi: 10.1007/s00421-015-3251-4. PubMed PMID: 26341091.

5.   Mattsson S, Jendle J, Adolfsson P. Carbohydrate Loading Followed by High Carbohydrate Intake During Prolonged Physical Exercise and Its Impact on Glucose Control in Individuals With Diabetes Type 1-An Exploratory Study. Front Endocrinol. 2019;10:571. doi: 10.3389/fendo.2019.00571. PubMed PMID: 31496994; PubMed Central PMCID: PMCPMC6712943.

6.   Chang CK, Borer K, Lin PJ. Low-Carbohydrate-High-Fat Diet: Can it Help Exercise Performance? J Hum Kinet. 2017;56:81-92.(doi):10.1515/hukin-2017-0025.

Sure, You May Lose Weight, But Will Going Low-Carb Impact Your Performance?

With the new year upon us and resolutions made, weight loss may be on your mind and with it low-carb eating as one potential way to cut back on calories. Before you decide how to go about losing weight, though, you may want to consider how cutting back on your carbohydrate intake may affect your ability to be physically active.

Although their long-term benefits on managing blood glucose levels are mixed (1), the popularity of low-carbohydrate diets has continued to rise among people with diabetes, especially those with type 1 diabetes (T1D). The exact carbohydrate intake that is “low” is not well defined, but under 130 grams (g) per day or <26% total energy intake or less than 3 g per kilogram of body weight daily is considered low by most (2, 3). Research on the glycemic impact of low-carbohydrate diets has largely involved highly motivated individuals with T1D engaging in frequent glucose monitoring and insulin adjustments to achieve tight glucose targets.

Adherence to such restricted diets is challenging, and carbohydrate-containing foods like whole grains, fruit, and dairy provide essential nutrients that many low-carbohydrate diets lack (3). The potential for diabetic ketoacidosis, hypoglycemia, altered blood lipids, and depleted glycogen (carbohydrate stores) when following very low-carbohydrate diets remains a concern (4); moreover, adults with T1D consuming less than 50 g per day may not react well to rescue glucagon used to treat hypoglycemia, likely due to a reduced liver glycogen (5).

As for exercise performance, your body’s preferential use of carbohydrate as a metabolic fuel during moderate and intense activities may make it difficult to perform optimally when you severely restrict your carbohydrate intake, especially prior to, during, and after exercise training and events (6). Prolonged endurance activities are limited by carbohydrates being available, and low-carbohydrate diets have the potential to limit muscle glycogen stores (7), particularly without a prior period of adaptation (such as a few weeks).

While your blood glucose use typically increases during most activities, the amount that is available when levels are in a normal range is very limited (only ~4 to 6 g of total glucose, depending on your size). While blood glucose production increases during activity from hepatic glycogen breakdown (glycogenolysis) or de novo (new) glucose formation (gluconeogenesis), the majority of carbohydrates muscles use comes from glucose stored as glycogen (8).

In the body, carbohydrates stores are limited in the skeletal muscles (typically 300 to 400 g) and the liver (more in the range of 80 to 100 g). Given the importance of carbohydrate availability during many sports and activities, pre-exercise levels of muscle glycogen in particular frequently determine how well you perform (9). Moreover, replacement of these stores during recovery depends on the availability of blood glucose, which can come directly from carbohydrates you consume or from new glucose made by your liver from metabolic precursors like lactate, pyruvate, alanine, and glycerol (10).

In addition, in people with T1D, effective glycogen repletion requires adequate food intake, blood glucose management, and insulin availability during recovery (11, 12). Elevated blood glucose can lead to lower liver glycogen storage (13). If you start exercising with low muscle and/or liver glycogen stores, you will likely need to take in carbohydrates during extended activities and may not perform as well. If you engage in activities that rely largely on muscle glycogen for fuel, such as many power–endurance and power sports, a low-carbohydrate diet may be detrimental to performance by limiting your ability to rapidly resynthesize adequate amounts of ATP, the energy molecule used for muscle contractions.

Adapted from Colberg SR, Nutrition and exercise performance in adults with type 1 diabetes. Canadian Journal of Diabetes, 44(8):750-758, 2020 (https://doi.org/10.1016/j.jcjd.2020.05.014)

References:

  1. Turton JL, Raab R, Rooney KB. Low-carbohydrate diets for type 1 diabetes mellitus: A systematic review. PloS one. 2018;13(3):e0194987-e. doi: 10.1371/journal.pone.0194987. PubMed PMID: 29596460.
  2. Feinman RD, Pogozelski WK, Astrup A, Bernstein RK, Fine EJ, Westman EC, et al. Dietary carbohydrate restriction as the first approach in diabetes management: critical review and evidence base. Nutrition. 2015;31(1):1-13. doi: 10.1016/j.nut.2014.06.011. PubMed PMID: 25287761.
  3. Seckold R, Fisher E, de Bock M, King BR, Smart CE. The ups and downs of low-carbohydrate diets in the management of Type 1 diabetes: a review of clinical outcomes. Diabetic Medicine. 2019;36(3):326-34. doi: 10.1111/dme.13845. PubMed PMID: 30362180.
  4. Leow ZZX, Guelfi KJ, Davis EA, Jones TW, Fournier PA. The glycaemic benefits of a very-low-carbohydrate ketogenic diet in adults with Type 1 diabetes mellitus may be opposed by increased hypoglycaemia risk and dyslipidaemia. Diabetic medicine : a journal of the British Diabetic Association. 2018:10.1111/dme.13663. doi: 10.1111/dme.13663. PubMed PMID: 29737587.
  5. Ranjan A, Schmidt S, Damm-Frydenberg C, Steineck I, Clausen TR, Holst JJ, et al. Low-Carbohydrate Diet Impairs the Effect of Glucagon in the Treatment of Insulin-Induced Mild Hypoglycemia: A Randomized Crossover Study. Diabetes care. 2017;40(1):132-5. doi: 10.2337/dc16-1472. PubMed PMID: 27797928.
  6. Cermak NM, van Loon LJ. The use of carbohydrates during exercise as an ergogenic aid. Sports Med. 2013;43(11):1139-55. doi: 10.1007/s40279-013-0079-0. PubMed PMID: 23846824.
  7. Yeo WK, Carey AL, Burke L, Spriet LL, Hawley JA. Fat adaptation in well-trained athletes: effects on cell metabolism. Appl Physiol Nutr Metab. 2011;36(1):12-22. doi: 10.1139/h10-089. PubMed PMID: 21326374.
  8. Jensen TE, Richter EA. Regulation of glucose and glycogen metabolism during and after exercise. J Physiol. 2012;590(Pt 5):1069-76. doi: 10.1113/jphysiol.2011.224972. PubMed PMID: 22199166.
  9. Areta JL, Hopkins WG. Skeletal Muscle Glycogen Content at Rest and During Endurance Exercise in Humans: A Meta-Analysis. Sports Med. 2018;48(9):2091-102. doi: 10.1007/s40279-018-0941-1.
  10. Jensen J, Rustad PI, Kolnes AJ, Lai YC. The role of skeletal muscle glycogen breakdown for regulation of insulin sensitivity by exercise. Frontiers in physiology. 2011;2:112. doi: 10.3389/fphys.2011.00112. PubMed PMID: 22232606.
  11. Buehler T, Bally L, Dokumaci AS, Stettler C, Boesch C. Methodological and physiological test-retest reliability of (13) C-MRS glycogen measurements in liver and in skeletal muscle of patients with type 1 diabetes and matched healthy controls. NMR in biomedicine. 2016;29(6):796-805. doi: 10.1002/nbm.3531. PubMed PMID: 27074205.
  12. Bischof MG, Bernroider E, Krssak M, Krebs M, Stingl H, Nowotny P, et al. Hepatic glycogen metabolism in type 1 diabetes after long-term near normoglycemia. Diabetes. 2002;51(1):49-54. doi: 10.2337/diabetes.51.1.49. PubMed PMID: 11756322.
  13. Hwang JH, Perseghin G, Rothman DL, Cline GW, Magnusson I, Petersen KF, et al. Impaired net hepatic glycogen synthesis in insulin-dependent diabetic subjects during mixed meal ingestion. A 13C nuclear magnetic resonance spectroscopy study. J Clin Invest. 1995;95(2):783-7. doi: 10.1172/JCI117727. PubMed PMID: 7860761.

What You Eat and Drink Affects Your Exercise Performance

How well you perform (physically) when you exercise is impacted in a number of ways by the intake of macronutrients—that is, carbohydrate, fat, and protein—whether you have diabetes or not (1, 2). Performance is directly affected by your calorie intake both during an activity and when you are recovering from it. Recovery, by definition, includes the entire time between the end of your last workout or competition and the start of the next one. In many cases, you may need to modify what you eat and drink for different types of training and competition, and periodized (that is, changing over periods of timing for training vs. competition) guidelines can lead you to the appropriate type, amount, and timing of intake of macronutrients and fluids to help you perform optimally (2).

All active people can experience a relative energy imbalance resulting from a mismatch between how many calories they’re consuming and how many they’re using during exercise and recovery. Many nutritional strategies for training and competition may involve pre-event, during-event, and between-event eating to address how to adequately replace calories and fluids. In addition to these and other factors (including muscle and liver glycogen storage and use, hydration, and micronutrient and electrolyte status), individuals with diabetes are additionally impacted by their blood glucose management (see figure).

Exercise carbohydrate requirements depend on an individual’s training status for a given event, as well as on environmental and other factors. When highly trained athletes compete in higher-intensity endurance events lasting up to 3 hours, carbohydrate remains the predominant fuel for the working muscles and its availability becomes rate limiting for performance, not fat availability (3). Anecdotally, according to active insulin users with diabetes, maintenance of their blood glucose levels at more normal levels improves exercise performance (4,5). You may need to adjust both your carbohydrate/food intake and insulin doses to prevent hypoglycemia or hyperglycemia during physical activity (6, 7). Supplementing with carbohydrate remains a proven strategy to increase endurance and intermittent sports performance in individuals without diabetes (8); carbohydrate intake has the greatest impact during activities that would lead to fatigue and/or low blood glucose (9), likely by providing an alternate fuel and sparing glycogen (stored glucose) in select muscle fibers (10). Glucose uptake into active muscles primarily occurs through a contraction-mediated, insulin-independent mechanism during activity, making its use as a fuel possible even if someone is insulin resistant (11).

Although protein use as a fuel during most activities is admittedly minimal, adequate daily intake of protein, mostly during recovery, may also impact overall performance. For most regularly training individuals, daily protein requirements are roughly 1.1 to 1.5 g of protein per kg (2.2 pounds) of body weight (roughly 15% to 20% of total calories) (12). Although aging by itself increases the need for quality protein, its intake is particularly critical in strength training athletes and individuals engaging in long duration aerobic training. If you fail to take in enough daily calories, your protein needs may be increased by exercise, whether or not you have diabetes.

Adapted from Colberg SR, Nutrition and exercise performance in adults with type 1 diabetes. Canadian Journal of Diabetes, 2020 Jun 2:S1499-2671(20)30152-0 (https://doi.org/10.1016/j.jcjd.2020.05.014)

References:

  1. Burke LM, Ross ML, Garvican-Lewis LA, Welvaert M, Heikura IA, Forbes SG, et al. Low carbohydrate, high fat diet impairs exercise economy and negates the performance benefit from intensified training in elite race walkers. J Physiol. 2017;595(9):2785-807. doi: 10.1113/JP273230.
  2. Burke LM, Castell LM, Casa DJ, Close GL, Costa RJS, Desbrow B, et al. International Association of Athletics Federations Consensus Statement 2019: Nutrition for Athletics. Int J Sport Nutr Exerc Metab. 2019;29(2):73-84. doi: 10.1123/ijsnem.2019-0065.
  3. Hawley JA, Leckey JJ. Carbohydrate dependence during prolonged, intense endurance exercise. Sports Med. 2015;45 Suppl 1:S5-12. doi: 10.1007/s40279-015-0400-1.
  4. Colberg S. The Athlete’s Guide to Diabetes: Expert Advice for 165 Sports and Activities. Champaign, IL: Human Kinetics; 2020. 382 p.
  5. Bally L, Laimer M, Stettler C. Exercise-associated glucose metabolism in individuals with type 1 diabetes mellitus. Curr Opin Clin Nutr Metab Care. 2015;18(4):428-33.  doi: 10.1097/mco.0000000000000185.
  6. Campbell MD, Walker M, Bracken RM, Turner D, Stevenson EJ, Gonzalez JT, et al. Insulin therapy and dietary adjustments to normalize glycemia and prevent nocturnal hypoglycemia after evening exercise in type 1 diabetes: a randomized controlled trial. BMJ Open Diabetes Res Care. 2015;3(1):e000085. doi: 10.1136/bmjdrc-2015-000085.
  7. Riddell MC, Gallen IW, Smart CE, Taplin CE, Adolfsson P, Lumb AN, et al. Exercise management in type 1 diabetes: a consensus statement. Lancet Diabetes Endocrinol. 2017;5(5):377-90. doi: 10.1016/S2213-8587(17)30014-1.
  8. Vandenbogaerde TJ, Hopkins WG. Effects of acute carbohydrate supplementation on endurance performance: a meta-analysis. Sports Med. 2011;41(9):773-92. doi: 10.2165/11590520-000000000-00000.
  9. Baker LB, Rollo I, Stein KW, Jeukendrup AE. Acute effects of carbohydrate supplementation on intermittent sports performance. Nutrients. 2015;7(7):5733-63. doi: 10.3390/nu7075249.
  10. De Bock K, Derave W, Ramaekers M, Richter EA, Hespel P. Fiber type-specific muscle glycogen sparing due to carbohydrate intake before and during exercise. J Appl Physiol (1985). 2007;102(1):183-8. doi: 10.1152/japplphysiol.00799.2006.
  11. Richter EA, Hargreaves M. Exercise, GLUT4, and skeletal muscle glucose uptake. Physiol Rev. 2013;93(3):993-1017. doi: 10.1152/physrev.00038.2012.
  12. American Dietetic A, Dietitians of C, American College of Sports M, Rodriguez NR, Di Marco NM, Langley S. American College of Sports Medicine position stand. Nutrition and athletic performance. Med Sci Sports Exerc. 2009;41(3):709-31. doi: 10.1249/MSS.0b013e31890eb86.

Be Physically Active (and More) to Boost Your Immune Response

In these recent challenging times, if we only could get a medication that would boost our immune system and response to viruses, lower all stress associated with being in a pandemic or post-pandemic, and treat most of the pre-existing health conditions that are associated with a higher risk of dying from COVID-19 or any other viruses, we would all be lined up for it! Guess what? We already have something that does all these things already—and that is physical activity.

Let’s consider its impact on how well your immune system works. While physical activity can boost your immune function, here’s what else we know about the immune system and all the lifestyles factors we can manage:

Exercise: A single workout may temporarily suppress your immune system, but chronic training (assuming it is not excessive) boosts immunity to the common cold, other viruses, and a whole host of pathogens (1). Being regularly active generally makes you less likely to get sick.

Stress: Any type of stressor, be it physical or mental, can weaken your immune system, most commonly through increases in levels of the hormone cortisol and other factors (2). Exercise overtraining raises cortisol levels and can make you more likely to catch a cold or the flu.

Sleep: Lack of sleep—particularly deep REM sleep—and short sleep duration cause a rise in cortisol levels that can dampen immune function (3). Many people with type 2 diabetes and overweight/obesity also have sleep apnea that interferes with getting quality sleep, making them more susceptible to getting sick. Better management of all of these conditions helps.

Nutrition: Chronic malnutrition lowers the ability of the immune system to function optimally. Low levels of vitamin D (which acts as a prohormone) in the bloodstream have also been tied with lower immunity, and many people with diabetes and older adults have low vitamin D status. Getting adequate vitamins, minerals, and calories in your diet can boost your immunity.

Alcohol: While a moderate intake of alcohol may give you some health benefits, abuse of alcohol suppresses your immune system (4). “Moderate” is one drink per day for females, two for males—and there is no rollover from one day to the next if you miss one!

Smoking: Tobacco smoking increases inflammation and lowers immune function, and it may also lower your immune response to certain vaccines. Quitting smoking can help restore immune function.

We also need to discuss how our bodies react to vaccinations. All of us are facing vaccinations for COVID-19 and potentially for other viruses in the future. You may be, like I was previously, assuming that vaccines work the same for everyone. In reality, there is no guarantee of a universal and equally protective response, and a whole host of factors (inside your body and out) can impact how well a vaccine actually works for you (5). Not surprisingly, all of the lifestyle factors listed above can impact the strength of your immunity post-vaccination, and making improvements in any/all of them can help. But your age can also have a negative effect.

COVID-19 is unlikely to be the last threat to our collective health, so it is worth discussing why we are more vulnerable to threats to our immune system as we get older. For starters, older adults have a less robust immune response to everything, including strains of influenza, and they suffer from a more rapid waning of antibodies. Basically, our immune systems are getting less robust and effective as we age—and that potentially impacts our response to vaccines.

Generally, older adults have a lesser immunity to any virus that they have been vaccinated against, and that will likely include the current global coronavirus once a vaccine is available. However, engaging in regular aerobic training improved flu vaccine responses in a group of older adults who had been previously sedentary (6): participants who did a regular moderate-intensity physical activity like brisk walking were 30 to 100 percent more likely to have an antibody response sufficient to keep them from getting the flu. Although research on this topic remains limited, exercise is likely to help boost the immune systems in people who are currently sedentary and start being active.

Other confounding health issues may make immune responses weaker when you are exposed to a virus or vaccinated. For instance, many seniors with diabetes develop kidney disease requiring dialysis. In these individuals, many fail to have an adequate immune response when given a vaccine for hepatitis B; how well it works depends on their age, how long they have been on dialysis, their diet, and other factors (7). In children (and adults) with type 1 diabetes, certain vaccines have been shown to be less effective, particularly when they also have celiac disease and consume gluten (8).

So, what can you do? Fight back by adopting the healthiest lifestyle that you can—one that includes being regularly moderately active—and stay as healthy as you can for when the next virus comes along. Protect yourself with a daily dose of exercise!

References:

  1. Cerqueira É, Marinho DA, Neiva HP, Lourenço O. Inflammatory Effects of High and Moderate Intensity Exercise-A Systematic Review. Front Physiol. 2020 Jan 9;10:1550. doi: 10.3389/fphys.2019.01550. PMID: 31992987.
  2. McEwen BS. Central effects of stress hormones in health and disease: Understanding the protective and damaging effects of stress and stress mediators. Eur J Pharmacol. 2008 Apr 7;583(2-3):174-85. doi: 10.1016/j.ejphar.2007.11.071. PMID: 18282566.
  3. Vgontzas AN, Zoumakis M, Bixler EO, et al. Impaired nighttime sleep in healthy old versus young adults is associated with elevated plasma interleukin-6 and cortisol levels: physiologic and therapeutic implications. J Clin Endocrinol Metab. 2003 May;88(5):2087-95. doi: 10.1210/jc.2002-021176. PMID: 12727959.
  4. Rodríguez-Rabassa M, López P, Sánchez R, et al. Inflammatory Biomarkers, Microbiome, Depression, and Executive Dysfunction in Alcohol Users. Int J Environ Res Public Health. 2020 Jan 21;17(3):689. doi: 10.3390/ijerph17030689. PMID: 31973090.
  5. Zimmermann P, Curtis N. Factors That Influence the Immune Response to Vaccination. Clin Microbiol Rev. 2019 Mar 13;32(2):e00084-18. doi: 10.1128/CMR.00084-18. PMID: 30867162.
  6. Woods JA, Keylock KT, Lowder T, et al. Cardiovascular exercise training extends influenza vaccine seroprotection in sedentary older adults: the immune function intervention trial. J Am Geriatr Soc. 2009 Dec;57(12):2183-91. doi: 10.1111/j.1532-5415.2009.02563.x. PMID: 20121985.
  7. Udomkarnjananun S, Takkavatakarn K, Praditpornsilpa K, et al. Hepatitis B virus vaccine immune response and mortality in dialysis patients: a meta-analysis. J Nephrol. 2020 Apr;33(2):343-354. doi: 10.1007/s40620-019-00668-1. Epub 2019 Nov 7. PMID: 31701375.
  8. Opri R, Veneri D, Mengoli C, Zanoni G. Immune response to Hepatitis B vaccine in patients with celiac disease: A systematic review and meta-analysis. Hum Vaccin Immunother. 2015;11(12):2800-5. doi: 10.1080/21645515.2015.1069448. Epub 2015 Sep 17. PMID: 26378476.

Pumping Up With Protein: Does This Work for Exercise and Health?

Protein is never a key exercise fuel, but it’s critical for other reasons. During most exercise, protein contributes less than 5 percent of the total energy, although it may rise to 10 to 15 percent during a prolonged event like a marathon or Ironman triathlon. Taking in enough dietary protein is important because such protein allows your muscles to be repaired after exercise and promotes the synthesis of hormones, enzymes, and other body tissues formed from amino acids, the building blocks of protein.

You should consume at least 12 to 35 percent of your daily calories as protein. For most people this means taking in at least 60 grams of protein daily.

About half of the 20 amino acids are considered essential in your diet, meaning that you must consume them or your body will suffer from protein malnutrition, which causes the breakdown of muscles and organs. Essential amino acids are found in meats, poultry, fish, dairy, eggs, and soy products. All plant-based foods besides soy are lacking one or more essential ones, but taking in combinations of plant sources (like rice and beans) can supply what you need.

Your body can make the rest of the amino acids itself (they are the nonessential ones). But you need to have enough protein in your diet overall to synthesize body proteins after workouts, which is a critical time for increases in strength, aerobic capacity, or muscle size.

Because protein is important to overall health but isn’t a major exercise fuel, you do need to worry about consuming enough, although it doesn’t have to happen right before or during an activity. You’ll get most effective restoration of liver glycogen if you keep your blood glucose levels in tight control after exercise. Consuming a small amount of protein along with carbohydrate (in a ratio of 1:4, or one gram of protein to every four grams of carbohydrate) after an activity may help you repair your muscles and get stronger more quickly.

Typically, an ounce of chicken, cheese, or meat has about 7 grams of protein.

Taking in more protein and slightly less carbohydrate after exercise can help keep your blood glucose more stable over time because protein takes three to four hours to be fully digested, and some protein is converted into blood glucose later. You can eat protein strategically to prevent later-onset hypoglycemia, which insulin users are more likely to get. Have some in your bedtime snack (along with fat and carbohydrate) to prevent nighttime lows after a day of strenuous or prolonged activity, if you use insulin.

Taking in some protein along with carbohydrate right after hard or long workouts may ­help ­your body ­replenish ­its ­glycogen ­stores ­more ­effectively. Though­ anyone ­who ­is ­getting ­older—­and ­that ­includes ­all ­of ­us—­can­ benefit from taking in enough protein, supplements are usually not the optimal way to get enough. Let me explain why.

As you get older, your body may need a more protein compared to when you were younger ­to form, maintain, ­and­ repair ­muscles­ and­ other ­body ­structures. Anyone who is doing regular exercise training also needs more protein to repair and build muscle, but you can usually get this amount (and more) when you’re eating ­a­­ balanced ­meal ­plan ­with ­adequate ­calories. To­ figure out ­how­ much ­you need, ­find ­the ­category ­that ­fits ­your ­age ­and ­training, ­and ­multiply ­your body weight­ (in pounds­ or­ kilograms)­ by­ the­ grams­ found­ in­ the­ corresponding table ­column.

TABLE           Recommended Protein Intake by Training Status and Age

Per Pound Body Weight         Per Kilogram Body Weight

Adults 19 to 50 years (inactive)          0.36 grams                              0.8 grams

Adults over 50 years (inactive)           0.5 grams                                1.1 grams

Endurance training                              0.55–0.64 grams                     1.2–1.4 grams

Strength training                                 0.68–0.77 grams                     1.5–1.7 grams

Calorie deprived (diets)                      0.73–0.82 grams                     1.6–1.8 grams

The biggest myth about amino acid supplements, and protein in general, is that you must load up on them to gain muscle. That’s just not true. The protein requirement for strength-training athletes may be about twice as high as normal, but most people in the United States already consume more than these higher amounts of protein in their daily diets.

To put it in perspective, to gain one pound of muscle mass a week (a realistic maximum), a strength-training athlete needs no more than 14 extra grams of quality protein per day. You can easily get this amount from these sources:

» About two 8-ounce glasses of milk

» 2 ounces of lean meat, chicken, fish, or cheese (which isn’t much)

» Slightly more than 2 eggs (only the whites contain protein)

Adequate intake of protein also helps to maintain lean body mass when you lose weight on a diet and can help you gain more muscle mass from exercise training.

Reference:  Excerpted from Colberg, SR, “Chapter 7: Eating Right for Exercise,” Diabetes & Keeping Fit for Dummies, Wiley, 2019.

Regaining Fitness in a Post-Pandemic World

Yes, I know we’re still dealing with a life-changing pandemic around the world and especially in most areas of the United States, but it is still worth thinking ahead to what comes next. Despite our discussion last month on non-gym fitness trends (focused around an article in Time [1]), it is more than likely that many of us have experienced a change (most often a decrease) in our daily physical activities and, subsequently, in our aerobic and muscular fitness levels.

A recent study (in 2020) conducted in Washington state (the state first impacted by curtailed daily activities) showed that strategies to mitigate the COVID-19 pandemic may be impacting physical activity and mental health, with those experiencing a decrease in physical activity also having higher levels of stress and anxiety (2). While a few of us may have gotten more active while working from home or having an altered daily life, the rest of us have had to curtail our activities—if not our workouts in public spaces like gyms and pools, at least our daily movement. When confined to our homes for working and learning, the lack of a daily commute to arrive at work or school by itself can remove a lot of daily steps that people would otherwise be taking, and mental stress and anxiety may be leading people to engage in other less healthy behaviors like stress eating.

Past research has demonstrated greater strength gains and blood glucose improvements from doing resistance training using harder weights or resistance than most people have access to at home, and regular participation is reinforced by supervision during training sessions and/or by social support arising from group exercise (2,3) What does that say about the future of working out at home, seldom if ever supervised and often alone? It may be hard to predict, but it is undeniable that doing any activity is better than none at all. Nonetheless, it is entirely likely that we will have lost some aerobic capability and muscular strength by the time we are able to restart our pre-pandemic activities.

So, what can we do to prepare to fully reenter the fitness world after it is finally considered safe to resume our pre-pandemic lifestyles? The best way to be ready is to stay as active as possible by doing anything you can from home or other safe venues now. That includes getting involved in virtual fitness classes, dusting off and using any exercise equipment you have at home, doing exercises using your body weight as resistance, and breaking up your sedentary time frequently, regardless of where you are working or learning.

Here are some other tips to keep in mind:

  • Find some time every day to be active, even if you only stand up during meetings instead of sitting or do easy exercises next to your desk.
  • Do more spontaneous activity, including getting up to break up sitting time for a few minutes every 20 to 30 minutes.
  • Use whatever equipment or household items you have access to in order to add a little resistance training to your day (aim for two to three days per week).
  • Use the latest technology or other tracking device to make sure you are getting in a minimum of activity every day (set daily and weekly goals for yourself).
  • Start out slowly and progress slowly over time once you can get back into doing more and harder activities as your top priority should be gaining fitness without injuring yourself.

Remember, when you’re starting out all over again, the same principles apply as when you began getting physically fit in the first place. Avoid the pitfalls that can lead to injury and demotivation, such as starting back at too high of an intensity. Hopefully, if nothing else, this pandemic will have led people to become more creative with their workouts and help everyone find ways to fit in more activity into their daily lives, during and after we’re through this rough patch.

References:

  1. Time magazine, July 15, 2020: https://time.com/5867166/covid-19-gyms-exercise/?fbclid=IwAR1DVNQEd03PaHdwZXSKlRNhYvlMosxVYg_Gfy5weAyk89Q5NTt82DRY8og
  2. Duncan GE, Avery AR, Seto E, Tsang S. Perceived change in physical activity levels and mental health during COVID-19: Findings among adult twin pairs. PLoS One. 2020;15(8):e0237695. Published 2020 Aug 13. doi:10.1371/journal.pone.0237695
  3. Dunstan DW, Daly RM, Owen N, et al. High-intensity resistance training improves glycemic control in older patients with type 2 diabetes. Diabetes Care. 2002;25(10):1729-1736. doi:10.2337/diacare.25.10.1729
  4. Dunstan DW, Daly RM, Owen N, et al. Home-based resistance training is not sufficient to maintain improved glycemic control following supervised training in older individuals with type 2 diabetes. Diabetes Care. 2005;28(1):3-9. doi:10.2337/diacare.28.1.3
  5. Dempsey PC, Larsen RN, Sethi P, et al. Benefits for Type 2 Diabetes of Interrupting Prolonged Sitting With Brief Bouts of Light Walking or Simple Resistance Activities. Diabetes Care. 2016;39(6):964-972. doi:10.2337/dc15-2336