Browse evidence-based analysis of health-related claims and assertions
Even though people do more work and feel less burned out chemically with 5-minute breaks, their heart rate and how hard they feel they’re working is about the same as with 2-minute breaks.
Descriptive
With 5-minute breaks, people can keep pushing with nearly the same force in every set, but with 2-minute breaks, their force drops more and more with each set.
Quantitative
The idea that the order your body burns food (alcohol first, then protein, etc.) tells you which food makes you feel full first is not true — eating these foods in equal amounts doesn’t make you feel differently full.
Even though people do more work with 5-minute breaks, their muscles produce less lactic acid than with 2-minute breaks, meaning they’re not as burned out from chemical buildup.
After doing hard leg pushes with 5-minute breaks, people’s muscles stay stronger and more activated afterward than after 2-minute breaks, meaning they don’t get as tired.
Even though alcohol makes your body stop burning fat, it doesn’t stop your blood fat levels from rising — they go up just as much as if you ate a fatty meal.
When doing intense leg exercises with 5-minute breaks between sets, people can do more total work than with only 2-minute breaks, because their muscles recover better.
Even though alcohol, protein, carbs, and fat affect your metabolism differently, eating any of them in similar amounts doesn’t make you feel hungrier or fuller, or change how much you eat next.
When you eat a meal with a lot of alcohol, your body stops burning fat and makes less of the hormone that tells you you're full, more than when you eat the same calories from other foods.
Eating a meal high in alcohol makes your body burn more calories right after eating than eating the same number of calories from carbs or fat, and protein does it a little less.
Whether you squat deep or shallow, doing squats twice a week for 8 weeks makes young tennis players stronger and leaner—depth matters for how much, but doing squats at all is what gets the job done.
Causal
Deep squats help young tennis players lose more body fat than shallow squats—after 8 weeks, they lose about a third of their body fat, while shallow squats only help them lose 15%.
Deep squats make young tennis players explode off the ground faster than shallow squats—after 8 weeks, they get about 20% faster at pushing heavy weights quickly, while shallow squats only help by 10%.
Deep squats don’t make leg muscles bigger than shallow squats if you do the same number of reps and same weight—muscle growth is about total work, not how deep you go.
For young tennis players, doing deep squats instead of shallow ones for 8 weeks makes them faster and stronger when pushing off the ground, and helps them lose body fat—without making their leg muscles bigger than shallow squats do.
The way your muscles fire when you do leg presses vs. leg extensions matches up with which muscles end up getting bigger after training.
People who do CrossFit might jump a little higher than weightlifters, but the difference is so small it could just be random chance.
Correlational
Whether you do CrossFit or lift weights regularly, your thigh muscles end up about the same size after years of training.
People who do CrossFit, lift weights, or just stay active all generate about the same peak power when jumping — no one group is significantly stronger or more explosive.
People who do CrossFit-style workouts can jump higher than regular active people, but they don’t jump noticeably higher than people who lift weights regularly.
People who have been doing serious workouts like CrossFit or weightlifting for years have bigger leg muscles than people who just stay active without formal training.
Just eating more protein doesn’t make you less hungry — but if you take out carbs and add fat instead, you feel much less hungry.
If you eat a high-protein, no-carb diet for two days, your body starts making a lot of ketones — enough to be in ketosis. But if you eat carbs with the same protein, you don’t.
Whether you eat a high-protein diet with carbs or without carbs, your body burns about the same number of calories — carbs don’t make you burn more energy.