Your body requires oxygen to turn fat and sugar into energy, as well as to carry out many other biochemical reactions necessary for life. Oxygen is carried through your body by a protein in your blood called hemoglobin.

There are several variations of the top 10 most physical sports; each variation depends on the criteria used to compile the list.

Whether on a college campus or in a city park, runners and skateboarders abound on a warm summer day. While runners still use the same basic equipment -- running shoes, shorts and headphones -- the sidewalk surfer's skateboard has evolved into the longboard.

Rock climbing and bodybuilding are two professional sports that share few similarities. While a rock climber focuses on performance, a bodybuilder focuses on aesthetics.

What is not to love about kayaking? Out in nature, potentially experiencing marine life depending on where you are, it's beautiful. And as if that wasn't reason enough to get after it, your upper body is in for one heck of a workout.

Riding a bicycle is not only fun, it’s an excellent form of aerobic exercise. A regular routine of cycling will get you in shape and keep you that way. You can achieve cardiovascular fitness, improved heart health and improved muscle strength and tone.

The mountain of deficits to overcome through occupational therapy after a CVA, also known as a cerebrovascular accident or stroke, can be daunting.

The Pendlay row is named after Glenn Pendlay, an Olympic weightlifting coach. The Pendlay version of the row is very similar to a standard barbell row, but there are some important differences. Your back is more horizontal during a Pendlay row and you set the weight down after each repetition.

Cycling provides a low-impact -- or non-weight-bearing -- exercise. Still, it's possible for a cyclist to suffer from a weight-bearing type of injury. It's just caused by a different mechanism of injury. Tendonitis can occur at any tendon site in your body -- areas that anchor muscle to bones.

The Centers for Disease Control and Prevention report that only 19 percent of teens are active in physical education classes across the country. Some teens simply don't participate in class, while others opt out entirely when P.E. is an elective. To entice more teens to come to and actively participate in P.E.

The key difference between hiking boots at your local retailer is the soles. Although they may all feel similar, there are significant differences. The secret to hiking soles lies in the midsoles. Between the rubber bottom and the inside of the boot are layers of protection that vary based on your activity.

While some climbers prefer steep outdoor crags with tough-to-negotiate overhangs, other climbers prefer the relative safety of indoor climbing. Whichever type of climbing you prefer, the muscles used are very similar.