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 high- or low-bar squats are better for gaining muscle and strength, how artificial sweeteners affect weight loss, whether ginseng increases testosterone levels, and more. 

There’s little difference between high- and low-bar squats, so do whichever you prefer.

Source: “A Biomechanical Comparison of the Safety-Bar, High-Bar and Low-Bar Squat around the Sticking Region among Recreationally Resistance-Trained Men and Women” published on August 6, 2021 in International Journal of Environmental Research and Public Health.

There are two ways to back squat: High bar and low bar. In the high-bar squat, the bar rests on your upper traps, and in the low-bar squat, your mid traps and rear delts

This subtle difference has spawned countless Internet kerfuffles, with zealots on both sides throwing around all manner of fitness cant to justify their stance. This study conducted by scientists at Nord University suggests this brouhaha is so much hot air.

The researchers had 14 recreationally trained folks perform a three-rep max (three reps with as much weight as possible) with three different squat styles: high-bar, low-bar, and safety bar squat

While the lifters performed the exercises, the researchers took a raft of measurements, including three-rep max weight, bar velocity at different parts of the exercise, joint angles and moments, and muscle activation of the spinal erectors, glutes, quads, hip adductors, hamstrings, and calves.

The results showed that joint angles differed slightly between squat styles, with the main difference being that weightlifters leaned further forward in the low-bar squat and stayed more upright in the high-bar squat.

In terms of weight lifted, the participants had the strongest three-rep max on the low-bar squat (214 lb/97 kg), with the high-bar squat coming in second (205 lb/93 kg), and the safety-bar squat coming in third (200 lb/91 kg). The glutes were also a tad more active during the safety bar squat than the high- or low-bar variations, though that may just be statistical noise.

Other than these (minor) differences, the results were identical with all three exercises.

In other words, it doesn’t matter which style of squatting you use—do whatever you find most comfortable. 

That said, there are a few situations that tilt the scales in favor of one variation or another. If you’re working around a lower-back injury, for instance, you may want to pigeonhole low-bar squats and stick to high-bar or safety bar squats until your back heals (low-bar squatting forces you to lean farther forward, putting more stress on your lower back). As I’ve written about before, there are probably benefits to rotating between different exercises every few months (including squats), which is how I designed my workout programs for men and women

If you squat multiple times per week, you could also use different variations on different days (high-bar on Mondays and low-bar on Thursdays, for instance). 

(And if you’d like even more specific advice about what exercises you should do, how often you should train, and for how many sets and reps you should do to reach your health and fitness goals, take the Legion Strength Training Quiz, and in less than a minute, you’ll get a completely personalized strength training program. Click here to check it out.)

TL;DR: There’s little difference between high- and low-bar squats. Do whichever squat style you prefer, or rotate through several variations in your program.

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Boosting your daily step count makes your cardio workouts more effective.

Source: “The Effect of Aerobic Training and Increasing Nonexercise Physical Activity on Cardiometabolic Risk Factors” published on October 1, 2021 in Medicine & Science in Sports & Exercise.

I’ve previously covered how walking helps you stay healthy and live longer, but according to the results of this study conducted by scientists at East Carolina University, it might also affect how well you respond to regular, formal exercise.

The researchers randomly split 45 middle-aged obese people into three groups. One walked on an incline treadmill for 40-to-50 minutes at an average heart rate of 125-to-130 beats per minute (a brisk walk) 3-to-4 times per week for 6 months, one did the same program and also increased their daily step count by ~3,000 steps per day (outside of their structured workouts), and the last group had the privilege of sitting on their butts being the control.

At the beginning of the study, all of the participants averaged 4,000-to-5,000 steps per day, which means the group who aimed to increase their daily step count was doing ~7,000-to-8,000 steps per day outside of their incline walking workouts. The researchers measured the participants’ body weight and waist circumference and did blood tests to measure several health markers such as cholesterol, insulin, and glucose levels at the beginning and end of the program.

Unsurprisingly, the results showed that people who were the most physically active lost more weight and improved their health and fitness more than the group that didn’t exercise. What’s interesting, though, is how much better the group did that boosted their normal step count.

Those who did just 3,000 more steps per day lost about twice as much weight (~2 lb vs. ~4 lb), decreased their waist circumference by twice as much (~1 in vs. ~2 in), lost more body fat (~1% vs. ~3%), decreased total cholesterol over twice as much (-5.4 mgdL vs. -12.3 mgdL), and improved several measures of cardiovascular fitness and metabolic health compared to those who only completed the walking workouts. 

All from walking about 30 minutes more per day. 

Now, you might be thinking, aren’t these benefits from just working out more? 

Yes and no. While exercising more is obviously going to help you get fitter faster, what’s interesting is the degree to which the extra steps helped. Although they only did about 30-to-40% more work, they saw a 50+% improvement in results (and remember that the extra steps were mostly from very low-intensity pottering around, not walking up an incline like in their regular cardio workouts).

Now, there are a few methodological quibbles worth noting. Most importantly, the differences didn’t reach statistical significance except for cardiovascular fitness. That said, given the strong trend in favor of the extra-steps group, it’s reasonable to conclude that there was some substantive benefit (even if it wasn’t statistically impressive). 

Second, if you exclude folks who didn’t stick to the protocol throughout the study, then the results would probably look even more impressive for the extra-steps group (no surprise—more work, more gains). 

Finally, you could also say that the absolute gains weren’t all that great either, especially after 6 months (also not surprising considering they didn’t change their diets). 

To me, the most important thing about this study is that it’s yet more evidence pointing to the outsize value of even seemingly “trivial” amounts of exercise. As I covered last week and in previous articles, even short, infrequent workouts yield massive dividends. 

Anywho, if you weren’t sold on walking before, recant your heretical ways and start legging it more often. 

TL;DR: People who increased their daily step count by ~3,000 steps in addition to doing 3-to-4 structured cardio workouts per week experienced disproportionately large improvements in body composition, cardiovascular fitness, and metabolic health compared to people who only did cardio. 

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There’s only one “right” way to phrase your weightlifting cues, and most people aren’t doing it. 

Source: “Acute and Long-Term Effects of Attentional Focus Strategies on Muscular Strength: A Meta-Analysis” published on November 12, 2021 in Sports (Basel).

A weightlifting cue is a mental mantra you recite during exercise that draws your attention to a particular aspect of your form. 

For example, “squeeze the bar” is a common weightlifting cue for improving your bench press, as it encourages you to maintain upper body tightness and aggressively drive the bar upward.

You can divide weightlifting cues into two categories: Internal cues and external cues. Internal cues direct your attention toward what you’re doing with your body (e.g. “hips up” in the squat), and external cues direct your attention toward how your movements impact an object in your environment (e.g. “push the floor away” in the deadlift).

Researchers—spearheaded by Dr. Gabriele Wulf—have proven many times over that external cues are superior to internal ones for improving performance in basically every sport imaginable. For example, external cues improve endurance, balance, agility, coordination, speed, movement efficiency, and throwing, kicking, and golf shot accuracy.

Most of these studies have focused on skill-based sports, and while one study showed that internal cues are about as good as external ones for improving leg extension performance (yawn), no researchers have carefully examined how interval versus external cues impact weightlifting performance . . . until now. 

In this review, the researchers combed through the results of seven studies and found that external cues boost strength significantly more than internal cues on the whole. Some of the studies measured obscure types of strength such as grip strength and finger strength, which aren’t necessarily applicable to weightlifters (researchers must work with what they have), but others showed that external cues also boosted strength in more relevant ways such as on exercises like the squat, deadlift, and mid-thigh pull

Most importantly, when the researchers looked at long-term data, they found that those who used external cues tended to gain more strength over time (particularly lower-body strength) than those who didn’t.

In other words, you don’t need to spend a decade studying to become a Bene Gesserit priest to interpret these results: if you want to get as strong as possible on basically any exercise, or better at any sport, use external cues instead of internal ones. 

For a catalog of my favorite cues, check out this article:

Complete List of Weightlifting Cues for Perfect Form & New PRs

Oh, and if the cues you fancy happen to be internal ones, you can tweak them to be external. “Keep your back straight” in the squat turns into “push your shoulders into the ceiling,” for instance.

Some people try to push back against this research by bringing up personal anecdotes or examples of accomplished athletes who prefer internal cues, but what you usually find is that these folks went from no cues to internal cues, which is obviously going to produce better results. That said, science shows external ones are still mo bettah. 

TL;DR: External weightlifting cues (“break the bar in half”) will help you get stronger than internal ones (“squeeze your pecs”).

Artificial sweeteners boost weight loss . . . make you gain weight . . . or maybe do nothing?

Source: “Effects of Nonnutritive Sweeteners on Body Weight and BMI in Diverse Clinical Contexts: Systematic Review and Meta-Analysis” published on March 25, 2020 in Obesity Reviews.

Weight loss ultimately boils down to calories in versus calories out

Foods and drinks that are sweetened with sugar tend to be really high in calories (150 per 12 oz for most sodas and energy drinks). 

Foods and drinks sweetened with non-nutritive artificial sweeteners tend to be much lower in calories. 

Ergo, concordantly, vis-a-vis, consuming artificially-sweetened fare should help you lose weight, right? 

Probably, but the research is a lot muddier than you might expect. 

Some studies show that people who eat artificially-sweetened foods and drinks lose more weight, and others show folks who consume more of these foods are actually more likely to be obese than those who don’t. 

To help cut this Gordian knot, researchers at Marista University of Mérida conducted a meta-analysis of 20 studies that involved a total of 2,914 participants and that lasted at least a month each. 

They found that people who consumed artificially-sweetened foods and drinks lost more weight (about 3 lb) and saw a greater decrease in body mass index (BMI) than people who didn’t. 

When the researchers dug deeper into the results, what they found was pleasingly in line with common sense: In and of themselves, artificial sweeteners have basically no impact on weight loss. They aren’t fat loss supplements, after all.

Where they can help, though, is if you’re replacing caloric sweeteners like sucrose or high-fructose corn syrup and not tracking calories, since you’re almost guaranteed to subconsciously consume fewer calories. 

When it comes to weight loss, then, artificial sweeteners are mostly benign.  

That said, I’m generally not a fan of wanton consumption of artificial sweeteners for two reasons: 

  • While the negative health effects are often exaggerated, there’s still some concern about what impact they might have long-term and there are safe, natural alternatives that taste just as good.
  • You could also argue that artificial sweeteners still fuel our hedonistic impulses to consume sweet-tasting foods. While it would be a stretch (and scientifically inaccurate) to say that artificial sweeteners encourage overeating calorific sweets, it’s undeniable that some people get weirdly attached to them and consume them in absurdly large quantities, and it’s probably wise to be wary of unhinged consumption of anything. 

And that’s why I don’t put artificial sweeteners in any of Legion’s products. It’s probably fine to consume them in small amounts (a few pieces of sugar-free gum aren’t gonna kill you), but I prefer to play it safe and stick to all-natural sweeteners most of the time.

Circling back to the study at hand, though, if we’re purely talking about weight loss, artificial sweeteners are just an easy way to reduce your calorie intake if you currently eat a lot of sugary foods. Nothing more, nothing less.

TL;DR: Artificially sweetened foods and drinks aren’t inherently “good” or “bad” for weight loss—they just help you eat fewer calories (although there are natural alternatives).

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Ginseng doesn’t boost testosterone.

Source: “The Effect of Ginseng Supplementation on Anabolic Index, Muscle Strength, Body Composition, and Testosterone and Cortisol Response to Acute Resistance Exercise in Male Bodybuilders” published on March 6, 2021 in Science & Sports.

A couple of years ago, a study conducted by scientists at the University of Edinburgh found that women experienced an increase in testosterone and DHEA (a precursor to testosterone) when they consumed 75 mg of red Korean ginseng for a week.

This was “exploratory research,” which means it was meant to just scratch the surface of a new topic and help researchers figure out what questions to test next. So of course supplement companies touted it as definitive sCiEnTaStIc evidence that ginseng gooses vitamin T and gives you whale boners and helps you pack on muscle faster than a roided hornet.

Some silly scientists from Islamic Azad University wanted to learn whether, you know, any of this was even remotely true, and so they conducted a study to determine whether ginseng could boost testosterone levels in male bodybuilders.

The researchers randomly split 20 male “natural” (drug-freeish) bodybuilders into two groups: A ginseng group and a placebo group. Both groups took two capsules twice daily. The only difference was that the ginseng group’s capsules contained 250 mg of ginseng, while the placebo group’s capsules were filled with two lines of coke cut with Drano® (just kidding, it was glucose powder).

Throughout the 6-week study, the participants continued to eat their regular diet and followed a 3-day upper-body strength training program.

At the beginning and end of the study, the researchers measured the participants’ BMI, waist-to-hip ratio, resting testosterone and cortisol levels, testosterone-to-cortisol ratio, and estimated bench and leg press one-rep max.

The results showed that supplementing with ginseng had no effect on body composition, strength, or hormone levels. Although people who took ginseng had ever-so-slightly higher testosterone levels post-workout, the difference was so small that it wouldn’t be enough to affect long-term muscle and strength gain.

The results of this study shouldn’t be surprising if you’ve been following my work for any length of time, but I think it’s important to dig up dead horses and give them a few whacks on occasion. Weak, preliminary, unreplicated studies like the one that kicked off this line of inquiry are fodder for unscrupulous pill and powder pushers, which is why it’s worth examining the stronger, more mature, replicable studies that often refute their marketing claims but are rarely mentioned.

Other than injecting some #dedication every week, there’s no supplement that reliably boosts testosterone levels. Until scientists discover something that does, the best ways to keep T levels topped off are to get plenty of sleep, minimize and manage stress, maintain a healthy weight, eat a balanced diet, lift weights, and allow your body time to recover from training.

(And if you feel confused about what supplements you should take to reach your health and fitness goals, take the Legion Supplement Finder Quiz, and in less than a minute, you’ll know exactly what supplements are right for you. Click here to check it out.)

TL;DR: Like every other purported “testosterone booster,” ginseng doesn’t actually boost testosterone, strength, muscle growth, or fat loss.

+ Scientific References