Jason Karp's Articles

Plateaus are boring. They are flat, unchanging, predictable. Many people who have been exercising for a while reach a plateau, during which their fitness level doesn’t c...

One of the main reasons for all of the attention being given to interval training in the fitness industry is that it can improve fitness quickly, which is great news for busy ...

There has been a lot of commotion lately about interval training. Once the training secret of the world’s best runners, interval training has gained some buzz in the fit...

Exercising in the heat can endanger health and impede exercise performance. Hot and humid days pose a particular risk: when it’s humid, the ability to dissipate heat is ...

Ever notice that some of your clients can do cardiovascular exercise for long periods of time but tire quickly when lifting weights? Or that others can lift heavy weights but ...

Anyone who grew up as a runner in New Jersey, as I did, would tell you that running during the summer in the Northeastern United States is no ordinary challenge. Some days...

WWhen I was a kid, I used to show girls my biceps. Boys do silly things to impress girls. As adults, both men and women search for countless ways to make their biceps, and the...

All the time, I hear fitness professionals tell their clients not to exercise above a certain heart rate, as if it were bad for people to run or bike fast. Target heart rate h...

One day, while I was running on a treadmill at the gym, a personal trainer approached the person next to me to share some advice. “Muriel,” she said, “if you...

There are more than 300 marathons just in the United States each year, with hundreds of thousands of people running them. Chances are that one or two of your clients want to d...

In 490 BC the ancient Greek hero Pheidippides ran from Marathon to Athens to announce the Greeks’ victory over Persia in the Battle of Marathon. When the modern Olympic ...

When you were young, you probably heard the jingle “The knee bone’s connected to the thigh bone; the thigh bone’s connected to the hip bone; the hip bone&rsq...

Do slight changes in body position affect muscle activation during strength exercises? The only way to truly know which muscles are used during an exercise is to measure their...

There’s a wrong way and a right way to do almost everything. For example, going down a park slide head first, throwing a paper airplane at your high-school teacher and...

Remember when you were in high school and your physical education (PE) teachers made you do push-ups, chin-ups and sit-ups? What about those long-forgotten Presidentia...

Remember when you were in high school and your physical education (PE) teachers—intimidating in their gray, cotton sweats, wielding whistles—made you do push-ups, ...

Weight training is an extremely beneficial form of exercise but can be confusing if you’ve never done it. Jason R. Karp, MS, PhD student, college lecturer and track and ...

Every day, fitness professionals are faced with a multitude of questions—on topics ranging from losing weight to rehabilitating injuries. While it is difficult to know a...