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Doing intense interval workouts for 8 weeks can change how your genes are switched on or off in your muscles — and this study says it affects over 14,000 spots in your DNA.
When young adults do intense workout bursts, take a 3-month break, then start again, their muscles' energy factories improve more the second time—even if their overall fitness doesn’t get much...
After a super intense 30-second sprint, sprint athletes have higher levels of certain chemicals in their blood and more acidic blood than endurance athletes during recovery — which means their bodies...
When athletes do their hardest sprints, how fast they go and how much lactic acid builds up in their blood can explain most of why their growth hormone spikes — it’s closely tied to how intensely...
Sprint athletes get a much bigger spike in their growth hormone after a hard 30-second sprint than endurance athletes do — their bodies react differently because of their training.
Doing fast, powerful exercises (like quick leg presses) is better than slow weightlifting for improving quick movements in older people, and it's safe if done right—but many still avoid it.
Right now, doctors mostly check muscle strength—like how hard you can squeeze—to diagnose weak muscles, but almost nobody tests how fast or powerful those muscles are, which might be missing an...
As we get older, our muscles' ability to generate power might slow down before we notice loss in strength or size — it could be the first sign our muscles are aging.
Scientists are suggesting a new word, 'powerpenia,' to describe when people lose muscle power as they age, get sick, or don't move much — and it's different from just losing muscle size or strength.
In older adults, how fast muscles can generate power matters more for staying steady on your feet and avoiding falls than how strong or big the muscles are — and it drops faster as you age.
Short, intense bursts of exercise (like sprinting) can boost heart and lung fitness just as well as longer, steady workouts — and take way less time.
Doing really intense sprints gives your body a big, quick boost in growth hormone—up to 17 times more—which helps protect your muscles and burn fat.
Sprinting helps keep your muscles fast and powerful as you age by improving how your brain talks to your muscles.
Sprinting helps build explosive muscle power because it makes your muscles push hard and move fast at the same time—like a car accelerating quickly—and that combo naturally boosts your ability to...
Being able to move quickly and powerfully—like jumping up or stopping a fall—matters more for everyday safety and independence than just being strong.
Your muscles' ability to generate power—like quickly standing up or catching yourself—depends on how well your nerves talk to your muscles. These nerve signals weaken with age and illness before your...
As we get older, we lose certain powerful muscle fibers faster than others, which can lead to weakness, falls, and trouble moving around — and this muscle decline can actually show how fast someone...
When you sprint, your body mainly uses fast-twitch muscles that give you quick, powerful bursts of energy, but they get tired really fast.
Muscle power — how fast you can use your muscles — might be a better sign of how long you'll live than just how strong your muscles are, because it shows how well your body can handle real-life...
Sprinting might help you stay younger on the inside by keeping your muscles, nerves, and metabolism in top shape.
After age 35, people get slightly worse at endurance sports each year—and that slowdown matches how much their lung and heart fitness drops. This suggests that losing aerobic fitness might be a big...
When top athletes get older, their performance drops at about the same rate in running, rowing, and swimming — which suggests their body systems all slow down together, not one faster than the rest.
If you're a top athlete over 35, your performance tends to drop by about half a percent each year — and this slow decline might be due to how our bodies naturally age, no matter the sport.
Your body's VO2 levels are the best way to measure how well you're performing during exercise.