, and as a result they operate less efficiently. Adding insult to injury, levels of testosterone and growth hormones that aid recovery also fall with age, says exercise physiologist Jonathan Dugas, co-author of the blog Science of Sport. © Chris
physiologist Jonathan Dugas, co-author of the blog Science of Sport (sportsscientists.com). Researchers call this sensation a rating of perceived exertion (PE). You feel it as fatigue in your legs, tightness in your chest, soreness in your muscles, aching
-product of normal metabolism, and as a result they operate less efficiently. Adding insult to injury, levels of testosterone and growth hormones that aid recovery also fall with age, says exercise physiologist Jonathan Dugas, co-author of the blog Science of Sport
