For most healthy adults, the Department of Health and Human Services recommends these exercise guidelines:

• Aerobic activity.

  Get at least 150 minutes of moderate aerobic activity a week. Or get at least 75 minutes of vigorous aerobic activity a week. You also can get an equal combination of moderate and vigorous activity. Aim to spread out this exercise over a few days or more in a week.

  For even more health benefits, the guidelines suggest getting 300 minutes a week or more of moderate aerobic activity. Exercising this much may help with weight loss or keeping off lost weight. But even small amounts of physical activity can be helpful. Being active for short periods of time during the day can add up and have health benefits.

• Strength training.

  Do strength training exercises for all major muscle groups at least two times a week. One set of each exercise is enough for health and fitness benefits. Use a weight or resistance level heavy enough to tire your muscles after about 12 to 15 repetitions.

Moderate aerobic exercise includes activities such as brisk walking, biking, swimming and mowing the lawn.

Vigorous aerobic exercise includes activities such as running, swimming laps, heavy yard work and aerobic dancing.

You can do strength training by using weight machines or weights, your own body weight, heavy bags or resistance bands. You also can use resistance paddles in the water or do activities such as rock climbing.

As a general goal, aim for at least 30 minutes of moderate physical activity every day. If you want to lose weight, keep off lost weight or meet specific fitness goals, you may need to exercise more.

Cutting down on sitting time is important, too. The more hours you sit each day, the higher your risk of metabolic problems. Sitting too much can negatively affect your health and longevity, even if you get the minimum suggested amount of daily physical activity. And some research has found that people who've lost weight may be more likely to keep off the lost weight by sitting less during the day.

Short on long chunks of time? Even brief bouts of activity offer benefits. For instance, if you can't fit in one 30-minute walk during the day, try a few five-minute walks instead. Any activity is better than none at all. What's most important is making regular physical activity part of your lifestyle.