One way to create a cross-training schedule is to learn more about different activities, especially if you aren't actually interested in a particular sport. This is especially helpful if you like to take group exercise classes at the gym but don't know how to make sure you aren't doing too much of one type of exercise.

High-impact Aerobics

High-impact aerobics are usually weight-bearing (body weight and gravity are factors) activities that are repetitive in nature and cause varying degrees of jarring, jolting, or pounding to one's musculoskeletal system. Examples of such activities include running or jogging, walking, jumping rope.

You should monitor your heart rate in an aerobics class just as you do in other activities. Doing this keeps you aligned with your fitness goals. However, manually monitoring your heart rate in class when the music is loud is difficult, and prone to inaccuracy. In the time that you stop and search for your pulse, your heart rate has already dropped significantly from what it was during exercise. The best way to monitor your heart rate in an aerobics class is to wear your heart-rate monitor and check your intensity level while you are moving. Some classes may not challenge you enough; others might push you too hard. In either case, it is good to know your preferred heart rates during exercise so that you can maintain that rate or RPE during a class.

Low-impact Aerobics

Aerobic routines are dance-style movements that get you moving and shaking, and your heart a-poundin'. In low-impact aerobics, you move horizontally (up and back, side to side) a lot, but without absorbing much jarring and pounding. You usually have at least one foot on the ground, which rules out the high-impact activities like jumping and hopping. In high-impact aerobics routines, you experience more vertical movements like hopping and jumping, which naturally have a stronger impact on you when you land. Weight-bearing exercise is good for you, so you should not be too quick to assume that the “impact” part of high and low impact is a good or bad thing. It depends upon your fitness goals. There are also combination high/low classes. If those are not available, try alternating between the two styles. Classes vary by styles of movement as well as intensity of exercise and type of music.

Aside from low-impact aerobic routines, there are other low-impact aerobic activities that are non-weight-bearing and that generate little, if any, jarring, jolting, or pounding to one's musculoskeletal system. Such activities include swimming, water aerobics, bicycling, rowing, cross-country skiing, stairclimbing, and using elliptical machines.

If you like dance, doing aerobics routines is great. If you have rhythm, coordination, and the ability to follow or remember dance-style movements, you will catch on quickly and have a great aerobic workout. However, if this is your first-ever dance class, or if you opted for tennis and skipped dance at summer camp, you could be in for a tough time.