Browse evidence-based analysis of health-related claims and assertions
When adults who already work out tried a special rest-pause weightlifting method for 6 weeks, their thigh muscles grew 11% thicker, while those doing regular weightlifting only saw 1% growth.
Causal
For people who already work out, taking short breaks during leg exercises leads to much better muscle stamina—27% better—than doing sets without breaks, which only improves by 8% after 6 weeks.
If you're already fit and do a special type of weight training called rest-pause for 6 weeks, you'll get just as strong as with regular training, and there's no real difference between the two methods.
When people who don't usually exercise do seated row exercises, their back and arm muscles work harder as they get tired, showing the body recruits more muscle fibers to keep going.
Descriptive
When people who don't exercise regularly get tired out before doing certain workouts, they can't do as many repeats afterward—about 25% fewer.
Quantitative
When people new to weight training exercise, their back and arm muscles show signs of getting tired over time, no matter how they warm up.
When people who don't exercise much do a special warm-up called pre-exhaustion before rowing exercises, their shoulder muscle gets tired faster than if they didn't do the warm-up.
Doing a pullover exercise before a rowing exercise doesn't make your back muscles work harder than if you just did the rowing exercise by itself, at least for people who aren't trained.
After a hard workout, the levels of copper and zinc in the blood go up the same way for both fit and not-so-fit male runners, even though their fitness levels are different.
When male runners do a short, hard workout, the amount of zinc and copper they lose in their pee doesn't really change much.
After hard exercise, zinc levels in runners' blood drop lower than before they started, and this happens even in people who don't exercise much, which might mean their bodies react slowly or lose zinc.
When male runners push themselves to exhaustion during intense exercise, their blood levels of zinc and copper go up right away—even when they eat the same foods—showing it's the body's natural reaction to hard workouts.
If you do the same total amount of exercise, three different workout styles—regular weight training, pre-exhaustion, and drop sets—all work just as well for building muscle strength, endurance, and size.
Different ways of lifting weights—like regular sets, pre-exhaustion, or drop sets—all work just as well for building muscle strength, endurance, and size if you do the same total amount of work. Changing the method doesn't give you better results.
When endurance athletes push themselves to exhaustion, their jumping ability gets worse in normal or low-oxygen air, but stays the same in hot conditions. This shows that different types of tiredness affect muscles differently depending on the environment.
When endurance athletes push themselves hard in hot conditions, their bodies produce more of one inflammation marker, but when they exercise with less oxygen, they produce less of another inflammation marker—showing different reactions to heat versus low oxygen.
Breathing less oxygen while exercising hard makes endurance athletes tire out faster because it weakens their muscles' ability to work properly, but getting hot doesn't really change how their muscles perform.
When guys who don't usually exercise try a special workout called pre-exhaustion training, they get 17% stronger in their legs—that's more than the 11% boost from regular workouts, probably because the special training targets the muscles more directly.
If untrained adult men do leg press exercises for nine weeks, their butt muscles won't grow much bigger, no matter how they do the exercises.
When untrained men do a specific type of weight training called pre-exhaustion, some parts of their thigh muscles grow more than others—the lower front part grows 44% thicker and the upper outer part grows 32% thicker.
For men who don't exercise much, doing regular leg press workouts with three sets at a moderate weight helps reduce overall body fat and thigh fat more than a different workout method, probably because they do more total work.
A shorter, easier leg workout gives the same muscle and strength gains as a longer, harder one for beginners, even though you're doing less overall work.
Doing a light warm-up set before lifting heavy weights might help you build more muscle and get stronger, according to some research that tried a similar but different approach.
When you tire out a muscle with one exercise before doing a bigger workout, you can't do as many reps in the big workout, so you end up doing less overall exercise than if you just did the big workout alone.