I just wanted to clarify some misconceptions about lower body strengthening. The main question that I usually get is Do I need to strengthen my legs if I'm a recreational or professional endurance or short distance runner?
THE ANSWER IS YES.
Lower body strengthening is very important for injury prevention and boosting performance. The majority of these athletes want to give more emphasis on upper body strength.
If that's the case, you really need to think before you act. The leg muscles, specifically work aerobically in running or any kind or sports related to running without any resistance to make those muscles work hard enough. That is why you need the strength/ power component to give those working muscle to fire under tension. You can test yourself simply by performing 2 sets of 15 repetitions of a lunge exercise. If you never resistance train before you will realize that your legs are not as strong as thought they were.