Before we learn about the different types of exercise, it is important to address differences in body-type.

There are three basic body types: Ectomorph, Endomorph and Mesomorph. Some of us gain weight with difficulty, some of us put on fat easily and others easily maintain a high percentage of muscle mass. The genetic differences between individuals is great. Body type has little to do with athletic ability or coordination, it simply relates to metabolism and genetic predisposition to gaining fat or muscle or staying lean.

Ectomorph. The Ectomorph generally has very high metabolic rate making it difficult for them to gain both muscle and fat. The Ectomorph is a naturally lean individual. Ectomorphs need less aerobics and should do anaerobic / strength building resistance training with repetitions in the 6 to 10 range.

Mesomorph. Mesomorphs are the individuals who naturally have excellent proportions of muscle mass and can gain muscle relatively easily through resistance training. Some mesomorphs are very lean and defined with "six pack abs" with little or no exercise. Many professional bodybuilders are typically mesomorphs.

Endomorph. Endomorphs are people who tend to put on fat easily. Endomorphs tend to have a lower metabolic rate and require more aerobics and higher repetitions in resistance training, preferably 12 - 20 reps, in order to burn more calories. Adding muscle through anaerobic exercise helps the endomorph's fitness tremendously by increasing their basal metabolic rate (muscle burns more calories at rest than fat).

There are two basic types or modes of exercise: aerobic and anaerobic. Aerobic exercise promotes cardiovascular fitness by raising your pulse to a targeted level. It is recommended that you exercise at your target heart rate for thirty minutes, three times a week. These excercises strengthen your heart, and allow the heart to pump more blood. Aerobic exercise improves the capacity of the lungs, helps control weight, and increases muscle and joint flexibility, making you less susceptible to injury. Some examples of aerobic exercise are walking, jogging, bicycling, swimming, racquetball, and aerobic dance. Aerobic exercise also helps to reduce risks associated with developing heart disease.

How long you perform aerobic exercise will depend on your goals, schedule, and physical condition: 10 to 60 minutes is an acceptable range of time. If your goal is body fat loss and you are appropriately conditioned, then longer is better: at least 30 minutes with 40 to 60 minutes preferred. Recent research shows that aerobic fitness levels can improve with as little as 10 minutes duration - as long as exercise is performed often: 2 to 3 times a day, 5 days a week. To balance general fitness, health, body composition, and scheduling concerns, 30 minutes is optimal for many people.

It is a common misconception that aerobic exercise tones/firms muscles. Actually it accomplishes very little toning/firming. In a typical aerobic workout, your active muscles perform hundreds of repetitions with a relatively low load/resistance placed on them; which is an ineffective toning/firming stimulus. Resistance exercise (weight training) is where real toning/firming of muscles occurs. Another misconception is that one must exercise aerobically at a low intensity to lose fat. Recent research has shown that we may exercise at any intensity for effective fat loss.

Anaerobic exercise focuses on specific muscles and their size, endurance, and strength. Weight lifting and resistance training are examples of anaerobic exercise. This form of exercise provide many benefits and is a good supplement to your aerobic work-outs. It may also increase bone density.

Resistance training is designed to improve either muscle strength or size. The muscle cells are purposely damaged through a process of overloading, the body reacts instinctively to repair the damaged cells so they can cope with any future overload, increasing their size and strength in the process. The muscles themselves do not actually increase in number, as some might think: the human body has a genetically defined number of muscle cells. Muscular fitness is a combination of strength, endurance and flexibility. Resistance training occurs over a short time frame and does not necessarily improve endurance capacity or for that matter flexibility. There may even be a decrease in endurance capacity because as the muscle cells grow the fluid between the cells, essential to oxygen transportation, is reduced.

Strength training is also important for your abdominal muscles - not the washboard abdomen, but the ones that come across the side. They’re called the oblique or lower-abdominal muscles. They should be strengthened because everything you do gets support from there. All leg and arm movement depends on having a strong spine, and the abdominal muscles support the spine. You should have a trained individual show you how; someone from a reputable health club, a physical therapist or an athletic trainer.

Remember, there are many benefits to exercise. It can help you sleep better, be more alert, handle stress better, and even look and feel better. Choose an exercise program that fits your particular needs, however, a complete exercise program should include some form of both aerobic and anaerobic exercise. If you're over thirty-five or have had medical problems, talk to your health doctor before beginning your exercise program. For more information on aerobic and anaerobic excercise, and the fundamentals of energy systems, please review our section on energy systems of the body. Always contact an exercise specialist if you are unsure which type of program to pursue.