UPDATE: I have had so many positive comments about last week's short quiz on nutrition, I decided to do another quiz - this time about exercise. So here goes:

1. True or false. The best kind of exercise for developing cardiovascular endurance must involve large muscle groups and is rhythmic in nature.Answer: True. Activities such as jogging, walking, cycling, aerobic dance and swimming all use the large muscle groups of the body and are rhythmic. The rhythmic nature of this type of activity helps return blood to the heart and develops the energy systems in the muscles so that cardiovascular endurance is increased.

2. True or false. It really doesn't matter what type of activity you choose for your exercise program, as long as it uses large muscles and is rhythmic.

Answer: True. In terms of developing endurance, any of the activities listed in question one are about equal. However, if you wish to get good at some activity, you must use that specific activity for your exercise program. For instance, to be a good runner requires running; to be a good cyclist, you must cycle. The reason for this is that part of the change that occurs with exercise is related to specific changes that occur in the muscles you use. Therefore, if you cycle, your cycling muscles become trained, but your jogging muscles are changed very little.

3. True or false. Everyone should work at about the same heart rate to get the same training effect.

Answer: False. As people get older, the maximum heart rate goes down about one beat per year. Therefore, if an older and a younger person worked at the same training heart rate, the older would be working at a higher percent of his maximum and he would feel much more fatigued than the younger. To compute your best training heart rate, subtract your age from 220 to get your predicted maximum heart rate. Then, multiply this number by 70 and 85 percent and use this as a "training zone." During the initial stages, work at the low end of the zone and increase the rate as you become more fit.

4. True or false. You can get an excellent training effect by working out only 10 minutes a day, three times a week.

Answer: False. Although you would probably make some measurable change in cardiovascular fitness level, a bit more would be advisable. Dr. Ralph Paffenbarger at Stanford University suggested that people use about 2,000 calories a week for maximum protection from cardiovascular disease. Since it takes about 100 calories to walk a mile, that translates into about 20 miles (or the same amount of time for other activities) a week. Other scientists have suggested that you burn about 10 percent of the number of calories you eat a day as a basic guideline to the total amount of exercise you do. This means that a person eating 2,400 calories a day should burn about 240 calories a day. In any case, get more active. Do more things.

Even a little bit of exercise is better than none. And spring is a great time to get started.

Garth Fisher is director of the Human Performance Research Center at Brigham Young University.