That helpful advice you hear at the gym may actually hurt you. We’ll help you distinguish the truth from the B.S

“Heat and vigorous exercise help you sweat out toxins “

You aren’t likely to purify your body of much of anything by sweating, whether in a hot yoga class or sizzling sauna, because all that’s in perspiration is water, salt and a smattering of electrolytes. Sweat glands sit in the skin and aren’t connected to other systems in the body, so it makes no sense that they would eliminate waste . The body does a pretty good job of getting rid of what it doesn’t need, largely through the liver, kidneys and digestive tract. There is nothing special you have to do to help, other than eat well, stay hydrated and keep fit so those organs can function properly .

“Running gives you wrinkles beacuae all that pounding breaks down collagen”

It’s an argument that could send just about anyone running for the nearest low impact class. Fortunately the idea doesn’t appear to have any hard science to back it up. It’s true that some runners an look a bit gaunt and somewhat craggier than their Pilates practicing counterparts. But this is largely due to having less body fat and spending more time in the sun.

“You should replace your sneakers every six months to avoid injury “

During a typical five mile outing, the average runner’s feet will strike the ground and compress the shock absorbent padding in her shoes about 7000 times. Cushioning and uppers will wear out, potentially providing less support for ankles and feet. And worn treads raise the risk for skids and falls. So replacing sneakers every 300 to 500 miles or roughly every three to six months, is a common and sensible guideline for avid runners.

Trainers who advise this as a general rule, however aren’t taking into account that people who exercise indoors or run fewer miles simply don’t put that kind of stress on their shoes. How to make sure? Every few months check the soles to make sure the treads aren’t worn.

Then take each shoe in your hands and give it a twist. If it twists easily, like a towel,your sneakers probably aren’t providing enough support .

“A cool down after your workout minimizes muscle soreness”

For years researchers believed that lactic acid buildup during rigorous exercise was what caused our muscles to ache later. their solution, a few minutes of walking or stretching to help disperse the lactate to other parts of the body. It’s a concept that’s alive and well today despite the fact that reams of research have proved that lactate buildup has little to do with post exercise muscle soreness. There is some evidence that after intense exercise, a cool down can help prevent blood from pooling in a person’s extremities and reduce their risk of becoming dizzy or passing out.

After a moderate workout, walking to the locker room will provide all the cool down a healthy person needs.