Weekly Research Roundup: Aging and Workout Recovery, Nicotine as a Pre-Workout, Cheat Meals and Binge Eating Disorder, and More

It’s estimated that there are over 2+ million scientific papers published each year, and this firehose only seems to intensify.

Even if you narrow your focus to fitness research, it would take several lifetimes to unravel the hairball of studies on nutrition, training, supplementation, and related fields.

This is why my team and I spend thousands of hours each year dissecting and describing scientific studies in articles, podcasts, and books and using the results to formulate our 100% all-natural sports supplements and inform our coaching services. 

And while the principles of proper eating and exercising are simple and somewhat immutable, reviewing new research can reinforce or reshape how we eat, train, and live for the better. 

Thus, each week, I’m going to share five scientific studies on diet, exercise, supplementation, mindset, and lifestyle that will help you gain muscle and strength, lose fat, perform and feel better, live longer, and get and stay healthier. 

This week, you’ll learn whether your recovery really declines as you age, how nicotine affects your workout performance, the pros and cons of “cheat meals” while dieting, and more.

People in their 50s recover from weightlifting as fast as people in their 20s.

Source: “Recovery from Eccentric Squat Exercise in Resistance-Trained Young and Master Athletes with Similar Maximum Strength: Combining Cold Water Immersion and Compression” published on September 10, 2021 in Frontiers in Physiology.

“Just wait until you’re 50 (or 40 or 30),” says so-and-so with a wan smile, “you won’t be able to bounce back like you used to.” 

Spend any time in the gym, and you’ll eventually hear this refrain. (Heck, maybe you’ve said it to a few cocksure whippersnappers.) 

There’s no doubt that the sands of time gradually grind our biological gears, but how much of this is really due to aging, flagging motivation, or some other factor? And does this really start in our 30s, 40s, or 50s as many people claim, or does it take more time for our wheels to start wiggling?

This study, published in the journal Frontiers in Physiology, took a stab at this question by dividing 16 competitive athletes into 2 age groups. The average age in the “young” group was ~22 years old, and the average age in the “old” group was ~52 years old.

Each group performed two workouts two weeks apart that were designed to cause as much muscle damage as possible. The workouts consisted of 9 sets of 8 reps of Smith machine squats with 70% of their one-rep max using a 4-second eccentric (lowering phase) and a 2-second concentric (lifting phase) for each rep, followed by one more set to failure (the point at which you can’t move the weight despite giving your maximal effort). 

After one workout, the participants followed a recovery protocol that involved ice-water immersion for 15 minutes and wearing lower-body compression tights for 48 hours (both of which improve recovery, at least in the short-term—more on this in a moment). After the other workout, they just went about their business without any special recovery techniques. 

The results showed that both the youngins and the oldsters recovered from these brutal leg workouts equally well. 

Whether you looked at the participants’ leg press and half squat strength, quad power, blood levels of creatine kinase (a marker of muscle damage), or perceived muscle soreness and physical readiness, there was almost no difference between groups. 

Ironically, the only significant difference was that the younger weightlifters reported greater muscle soreness and lower physical readiness after their workouts than the older participants. While this may seem baffling, it makes sense since the younger weightlifters were a bit stronger and more powerful to begin with, and thus were probably able to subject their muscles to more of a thrashing compared to their older counterparts.  

Another interesting wrinkle from this study is that the “special” recovery protocol of ice baths and compression tights yielded almost no benefit versus doing nothing after workouts. While they helped the weightlifters feel a little more recovered, they didn’t improve any objective measure of recovery. That said, one reason for this may be that the study duration was too short and the sample size too small to see meaningful improvements. The evidence behind compression garments for recovery is promising, but substantially less so for ice baths.

Finally, there’s one more datum worth considering when you interpret these results: All of the participants were fit, active, competitive athletes, not couch potatoes, and other studies have also shown that fit older folks recover about as fast as unfit younger ones. The same can’t be said for unfit, sedentary older people, whose recovery abilities do flag over time.

This study also underlines the importance of easing into a new workout routine if you’re currently sedentary or coming back from a long layoff. Restrain your eagerness in the beginning, give your body time to improve its recovery abilities, and gradually increase your volume, intensity, and frequency from there.

(And if you want a fitness program specifically designed to help absolute beginners at any age and fitness level get in the best shape of their life, check out my newest fitness book for men and women, Muscle for Life.)

TL;DR: Middle-aged and older people recover about as well as younger people from weightlifting provided they stay active, fit, and healthy.

The bench press trains different muscles in men and women.

Source: “Understanding Bench Press Biomechanics—Training Expertise and Sex Affect Lifting Technique and Net Joint Moments” published on December 23, 2021 in Journal of Strength and Conditioning Research.

Men and women are more similar than they are different, but we do diverge in a few important ways that can impact the benefits we get from exercise.

A recent example of this comes from a study conducted by scientists at the Norwegian School of Sport Sciences. The researchers recruited 22 recreationally trained weightlifters (13 men and 9 women) and 12 competitive powerlifters (6 men and 6 women) and had them perform a 6-to-8 rep max set of bench press.

The results showed two things: 

1. The chest muscles (the pectoralis major to be precise) were significantly more active in men than women, and the triceps (especially the long head) were more active in women than men.
2. The powerlifters generally used more efficient technique than the recreational weightlifters (unsurprising).

In other words, the bench press seemed to be more “pec dominant” in men and “triceps dominant” in women. That said, men also tended to adopt technique that would emphasize the pecs over the triceps and vice versa for women, so it’s possible these differences would partially disappear with practice. 

From my perspective, this is yet more evidence in favor of training muscle groups with a handful of different exercises, as one may not be enough to maximize strength and muscle gain. 

For example, if you want to develop your “pushing” muscles (chest, shoulders, triceps), you’ll likely get the best results by doing a few compound exercises, such as the bench press, incline bench press, and overhead press and a few isolation exercises such as the dumbbell or cable fly, triceps pushdown and overhead press, and dumbbell or cable side raises. This is also how I structure the training programs in my bestselling books and programs, Bigger Leaner Stronger for men and Thinner Leaner Stronger for women.

Exactly how many sets and reps you do and how you distribute these throughout the week depends on your goals, preferences, and schedule, but if you want even more specific advice on how you should train, take the Legion Strength Training Quiz! In less than a minute, you’ll know the perfect strength training program for you. Click here to check it out.

TL;DR: The bench press was slightly better at training the pecs in men and the triceps in women, but the differences were small. Your best bet is to train both muscle groups with a variety of exercises (including the bench press).

Nicotine isn’t a good pre-workout supplement. 

Source: “Effect of Nicotine on Repeated Bouts of Anaerobic Exercise in Nicotine Naïve Individuals” published in February 16, 2018 in European Journal of Applied Physiology.

Most everyone knows two things about cigarettes: 

1. They’re addictive and bad for you
2. They’re powerful stimulants

That second point—cigarettes’ stimulatory effects—are due to tobacco’s nicotine content. 

Although nicotine is highly addictive, there’s still some debate about how unhealthy it is in and of itself. On the one hand, studies show nicotine can cause negative health effects, but many of these were involved animals (not humans), short timeframes, and unrealistically high doses. Others contend that while pure nicotine probably isn’t that bad for you, its real demerit comes from keeping people hooked on tobacco, which is the delivery vehicle for all of the bad stuff. 

But who cares about all of that if it helps you lift a few more grams or iron or run a little faster, amiright? 

Several studies have found that nicotine improves reaction time and concentration, promotes relaxation, and enhances attention, cognition, and memory. These perks could theoretically improve performance, but studies that have directly examined nicotine’s effect on athleticism have been hit or miss. 

One study showed it improved leg strength, one showed it improved reaction time but actually reduced strength, and another showed it increased perceived mental fatigue but had no impact on actual performance. 

Scientists at James Cook University conducted this study to help athletes get a better idea of the pros and cons of nicotine as a pre-workout supplement.

A quick caveat before I continue: I don’t take nicotine and don’t recommend you do, as it’s one of the most addictive substances known to man, and I’m generally opposed to ingesting anything that catalyzes dependance or wanton consumption. That said, I also think it’s worth carefully examining all potential performance-enhancing supplements, including nicotine, so we can better understand their pros and cons instead of dismissing them out of hand because they happen to be found in tobacco products. With that disclaimer out of the way, on to the study . . . 

The researchers recruited 16 healthy men who hadn’t smoked more than 10 cigarettes in the past 5 years and who trained for power or strength at least 3 times per week.

The study design was labyrinthine and it’s not worth exploring every nook and cranny, but the key takeaways are that the participants did two workouts, both of which involved a reaction time test and a Wingate test (which consists of two 15-second all-out cycle sprints with a 3-minute rest in between). The participants took a placebo before one workout and 5 mg of nicotine before the other.

The researchers found that nicotine increased peak power output by about 10% during the Wingate tests compared to the placebo, and increased average power over both tests but to a lesser degree. It also bumped up the participant’s heart rate and blood pressure and reduced their perceived tiredness, irritability, and nausea on average (although a few people experienced more nausea), but had no effect on reaction time. 

About what you’d expect from a powerful stimulant.

Why do I say that nicotine’s not a good pre-workout supplement, then? 

First, as you saw a moment ago, the body of evidence regarding nicotine and athletic performance is underwhelming. Only two studies have found benefit and all of them only lasted a short duration, involved very few subjects, and were on men only, so we don’t know how well it would work in women.

Second, most of the participants (11 out of 16) in this study knew when they were taking nicotine versus the placebo, which muddles the results and also illustrates how difficult it is to objectively “blind” subjects to what they’re taking, especially when it comes to drugs with powerful psychological effects. This makes it much more likely that they benefitted somewhat from the placebo effect.

Third, there are nicotine’s side effects. Although consuming nicotine through patches, gum, tablets, or dissolving strips (like in this study) is probably less addictive than inhaling it (either through cigarettes, cigars, pipes, or e-cigarettes), there is still a significant risk of addiction with any form of nicotine. Other side effects include mild to extreme jitters, nervousness, elevated heart rate, and nausea.

For example, in one of the studies I mentioned a moment ago, 12 out of 18 participants experienced mild to severe side effects including nausea, vomiting, dizziness, confusion, tiredness, and tremors. One of the participants in the present study also accidentally consumed too much, became sick, and performed worse in his workouts. 

Mediocre effectiveness . . . high risk of nausea, vomiting, and addiction . . . questions over the proper dosage and administration . . . I do not like this “supplement,” Sam I Am.

Instead, I take and recommend safe, natural performance-enhancing supplements, like those found in Legion’s 100% natural pre-workout supplement, Pulse.

Or if you aren’t sure if Pulse is right for you or if another supplement might be a better fit for your budget, circumstances, and goals, then take the Legion Supplement Finder Quiz. In less than a minute, it’ll tell you exactly what supplements are right for you. Click here to check it out.

TL;DR: This study found that taking nicotine slightly boosted sprint power output, but when weighed against the very high potential for side effects and addiction, the results are unimpressive. 

The contraceptive pill doesn’t hinder your ability to build muscle, gain strength, or lose fat.

Source: “Molecular markers of skeletal muscle hypertrophy following 10 wk of resistance training in oral contraceptive users and nonusers” published on December 1, 2020 in Journal of Applied Physiology.

Many women worry that the contraceptive pill will hamper their progress in the gym, but this study shows this probably isn’t the case.

Thirty-eight untrained women with regular menstrual cycles took part, 20 of whom took daily oral contraceptive pills. All of the participants completed a 10-week training program that involved 3 full-body workouts per week. 

At the beginning and end of the study, the researchers measured the women’s leg strength, quad size, lower-body power, and body composition and took muscle biopsies from each woman’s quad muscles. 

The results showed that both groups experienced similar changes on every measure. The group taking contraceptives gained a little more muscle than the group that didn’t (~3.7% vs. ~2.7%), whereas the group not taking the Pill lost a bit more fat (~2 lb. vs. ~¼ lb.), but neither of these results were statistically significant or meaningful in the real world. 

Additionally, the muscle samples taken from women on contraceptives tended to show a greater rise in special proteins associated with muscle growth, but this was only statistically significant for two of them (MRF4 and androgen receptor protein). While that’s interesting, it didn’t translate into any tangible benefit in this study.

These results demonstrate what several other studies have shown—contraceptive pills don’t seem to meaningfully affect muscle growth, strength gain, or fat loss.

The researchers also suggested that the contraceptive pill may improve performance slightly, although this would need to be weighed against the potential side effects, which can include nausea, headaches, mood changes, irregular periods, and reduced sex drive. If the researchers are correct, though, and contraceptives do give you a slight boost in performance, I wouldn’t be surprised if this catches the attention of anti-doping authorities. 

TL;DR: Oral contraceptives don’t seem to hinder your ability to build muscle, gain strength, or lose fat. 

Do cheat meals lead to eating disorders? The devil is in the details.

Source: “A thematic content analysis of #cheatmeal images on social media: Characterizing an emerging dietary trend” published on January 11, 2017 in The International Journal of Eating Disorders.

For many fitness fiends, the “cheat meal” has become an inviolable dietary ritual. The way most people practice “cheating” is to eat one cheat meal per week, following their normal meal plan to a T the rest of the time. 

This seems like a clearheaded solution to an obvious problem: It allows you to enjoy large portions of treats and high-calorie indulgences while still making progress toward your goals, since the “damage” is limited to just one meal per week.  

It’s easy to let this practice get out of hand, though, which this study shows can inflame eating disorder-like symptoms, psychological distress, and binge eating. 

Researchers at the University of Toronto scoured Instagram for posts tagged with the term “#cheatmeal,” uncovering 1.6 million posts (the same search now unearths more than 4.2 million posts). 

Here’s what they found after analyzing the posts:

• 55% of the resulting images depicted a volume of food consistent with a binge eating episode, with some meals exceeding 9,000 calories.
• 44% of the posts that had a caption included text that espoused overindulgence and eating massive quantities of food in a single sitting (#bigdogsgottaeat, bruh)
• 35% gunned for a strong commitment to exercise  
• 22% glorified restraint and having enough willpower to stick to a rigid diet and training protocol (when they weren’t cheating, presumably)

For example, some of the most common phrases used to describe cheat meals included “feast,” “heaven,” “obsessed may be an understatement,” and “I don’t want to look back one day and think ‘I could have eaten that’.” 

Another recurring theme within the captions was the loss of control while consuming cheat meals—another hallmark of binge eating disorder. For example, under an image of 10 jars of nut butters, the poster wrote, “I can’t control myself around these bad boys on prep, I need to hide them.” Another caption for an image displaying leftover slices of a pizza quipped, “oops I did it again.”

What really troubled the researchers wasn’t the disposing of large amounts of food, but the spirit in which this hedonism was carried out. 

While this kind of behavior seems normal in the bodybuilding echo chambers of Instagram, it’s hard to distinguish from a bona-fide binge eating disorder.

A common motif in all of these posts was the framing of cheat meals as a “reward” for grueling exercise and dietary asceticism. Instead of viewing exercise, health, and self-possession as the end goals, these folks framed them largely as tools to allow for ever larger cheat meals. To paraphrase Socrates, these folks are living to eat and drink, not eating and drinking to live. 

At this point you might expect me to denounce cheat meals altogether, but I still think the practice has merit when used correctly. 

Building a body you can be proud of will always require some dietary restraint, which inevitably leads to some cravings. Instead of splurging with a supersized “cheat meal” or “cheat day,” I practice and advocate what I refer to as treating:

You stick to your meal plan “perfectly” (good enough) for a set period of time, usually a week or so, and then enjoy a bit of “off-plan” eating—usually as a single “cheat meal”—even if you’re not hankering for it. 

Think of it like controlled burning, where . . . forest experts? Foresters? Silvologists? Whatever . . . burn away dead grass and trees, fallen branches, and undergrowth to prevent a raging inferno.

Similarly, by regularly immolating your dietary demons when they’re just cuddly little kidlets, you can avoid facing them as a gang of belligerent teenagers on the warpath.

This approach is preferred by most people who have achieved an elite level of fitness, and there’s good scientific evidence of its effectiveness as well. For instance, studies on “diet breaks” have consistently shown that people tend to lose more fat when they alternate between periods of following a diet plan closely and loosely.

You can check out this article to learn more about how to properly “treat,” but here are the highlights: 

1. Treat yourself just once or twice per week.
2. Try not to exceed your daily energy expenditure (no 10,000 calorie challenge nonsense).
3. Try to keep your dietary fat intake under 100 grams for the day.
4. Drink alcohol intelligently.

Unlike the food orgies practiced by the appetitive lotus-eaters of Instagram, treating is sustainable, healthy, and productive, and what I do personally and recommend in my fitness books for men and women.

(And if you’d like more information about exactly which diet to follow to reach your fitness goals, take the Legion Diet Quiz and in less than a minute, you’ll know exactly what diet is right for you. Click here to check it out.)

TL;DR: Unhinged “cheating” like you’ll see on Instagram is hard to distinguish from binge eating disorder, and you’re better off periodically including planned, calorie-controlled “treats” in your diet if you want to build and maintain a healthy body and headspace.