What activities tend to be hardest on the knees?
The ones that involve excessive flexing, especially with weights, such as a full squat or leg press. Or any type of exercise that involves sudden stops, starts and pivots, or potentially awkward jumps and landings - such as basketball, tennis, soccer, racquetball and football. Jumping exercises called plyometrics, which focus on increasing muscle power, can also be tough on the knee joint. A good example of this type of exercise would be a basketball player repeatedly jumping up to touch the face of the backboard. Jumping places a force of two to three times your body weight across your knees, which naturally increases the potential for injury, and people with knee problems would do best to avoid jumps that require a very deep knee bend or could torque the knee on landing. A better type of exercise may be "low plyometrics," like jumping rope or even jumping on a trampoline, depending on how stable your knee is.
Is jogging hard on the knees?
Recreational jogging in moderation actually is not hard on problem free knees. (When we say jogging, we are referring to a slower-paced, short-distance run.) A lot of people say, "Oh, it's going to cause arthritis," but mild to moderate running or jogging hasn't been shown to increase the incidence of osteoarthritis. On the other hand, a history of knee injury is one of the biggest factors in long-term arthritis risk.. So if you've injured your knee and are jogging, then you might run into trouble down the road.
I would say that running cross-country or on uneven surfaces can be particularly hard on the knee especially if you have some inherent misalignment in the joint. If this is the case and you can't live without your morning workout, try running on a treadmill. Treadmills soften the impact of your step while providing a flat and even surface.