Exercise -- it's part of what's necessary to lose weight. But, for extremely obese men and women, even light exercise can sometimes prove too much on tendons and ligaments.

A study published in Medicine & Science in Sports & Exercise reveals that light exercise, such as as regularly-paced walking, can increase a person's risk of osteoarthritis if they're obese. Overweight walkers were found to have 51 percent more muscle torque -- the force that pulls on muscles, tendons, and ligaments and leads to the breakdown of cartilage -- than people whose weight was in a healthy range.

This doesn't mean that exercising is too dangerous and should be avoided if you're exceptionally heavy. Rather, it merely highlights the fact that extra care needs to be taken, which should include a discussion with your doctor and/or specialist about the right fitness protocol for you.