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Taking a weekly 6 mg dose of the drug sirolimus doesn't help older adults get extra benefits from exercise — and might even cancel out some of the gains they'd normally see.
Doing strength and cardio exercises at home for 13 weeks helps older adults (65–85) get stronger in their legs and move better, whether or not they're taking a drug called sirolimus.
Older adults taking a weekly 6 mg dose of sirolimus while exercising for 13 weeks may have more side effects overall than those taking a fake pill, including a serious lung infection like pneumonia,...
In older adults who don't move much, taking a weekly rapamycin pill might slightly weaken the benefits of a 13-week home exercise program on leg strength and mobility, according to some detailed...
When men push with their legs using different exercises but at the same knee angle, their thigh muscles turn on in a similar way, even though one exercise uses more joints than the other.
When healthy guys push with their legs, the electrical activity in one specific thigh muscle (vastus lateralis) goes up steadily with how hard they push — unlike two other thigh muscles — so it might...
When healthy guys push with their legs at a 90-degree bend, their quad muscles don’t fire in a straight line with how hard they push — the muscle activity changes unevenly as they push harder from...
When strong guys do fast squats with heavy weights, their butt muscles kick in later during the upward push compared to when they use lighter weights — it’s like their body adjusts how it uses those...
When strong guys do fast back squats with heavy weights, their butt and hamstring muscles work harder the heavier the weight gets — especially the butt muscle, which really kicks in when the weight...
When strong guys do fast squats, their thigh muscles turn on in a set order—one muscle first, then another, then a third—and that order doesn’t change no matter how heavy the weight is.
When strong guys do fast squats with heavy weights, their leg muscles don't work harder the heavier the weight gets—until they go all the way up to their max. At max weight, two of the three main...
When strong guys do squats as fast as they can, the heavier the weight, the slower they move — even if they're trying to go fast. The heaviest weights always result in the slowest lifts, and this...
For male bodybuilders, changing the knee bend doesn't really affect a key thigh muscle's stiffness if the hip stays in the same position — but changing the hip position does seem to matter more.
In male bodybuilders, the top part of a big thigh muscle reacts more to hip position than the lower parts when the knee is bent slightly, showing that the muscle doesn't work the same way from top to...
When bodybuilders push hard with their legs, the stiffness in a key thigh muscle changes depending on leg position—but the usual muscle activity sensors (EMG) don’t pick up these differences,...
When male bodybuilders flex their knees and push without moving their legs, the front thigh muscle feels stiffer than a neighboring muscle — and this difference depends on how much the hip is bent.
When male bodybuilders flex their knees at a 30-degree angle, the upper part of a specific thigh muscle gets stiffer if their hips are straighter, suggesting how stretched the hip is can change how...
When lying down, your leg muscles don't get stronger even if one key muscle gets longer — and that's mostly because your brain isn't fully turning on those muscles, not because opposing muscles are...
When healthy guys lie on their back, their thigh muscles can push harder than when they're sitting — probably because the position stretches one key muscle and lets it work better.
When guys sit down and squeeze their quads as hard as they can, their hamstrings resist more than when they're lying flat — probably because the hips are bent.
When healthy guys push with their legs, they're just as strong sitting or lying down—even though one position stretches the muscle more. That means muscle strength isn’t just about how stretched the...
For male bodybuilders doing leg extensions, bending the hips to 40 degrees might work the top part of the front thigh muscle better than bending to 80 degrees, based on brain scan-like results...
Just because your quad feels like it's working hard during leg lifts doesn't mean that part of the muscle is actually lighting up — especially in people who train regularly.
When male bodybuilders do leg extensions with their hips bent at 80 degrees, the lower part of their front thigh muscle works harder than the middle part, according to MRI scans.