The mechanics of weight loss seems like one of life’s biggest mysteries, but the math couldn’t be simpler: consume fewer calories than you use, and you'll lose weight.

The amount of calories a body burns on a daily basis depends on a number of factors — age, weight, gender and activity level. The broad range for adults is 1,600 to 3,000 calories per day. Your body uses calories for everything from digesting food to sitting, but it’s the more vigorous activities that burn the most.

The basic rule of thumb for weight loss is that a reduction of 3,500 calories results in the loss of one pound. So, for example, if you hypothetically cut 500 calories per day, you would lose one pound in a week. On the other hand, if you kept your calorie intake the same but you burned an extra 500 calories per day with exercise, you would also lose a pound in a week.

Which goes to say that if you add one of these calorie-burning activities to your daily routine (and don’t make up for it with a candy bar) you could lose roughly two pounds per month. It may not have you bathing-suit ready by the first beach day, but keep it up and by the end of the summer you could potentially have lost almost nine pounds! Not to mention reaping the other health benefits of exercise, a nice dose of vitamin D, and the unique pleasure that only fresh air delivers.

You can burn 300 calories with each of these activities*:

  1. Frisbee: 80 minutes
  2. Volleyball (non-competitive): 80 minutes
  3. Archery (non-hunting): 69 minutes
  4. Horseback riding: 60 minutes
  5. Walking (3.5 mph): 60 minutes
  6. Planting seedlings, shrubs: 60 minutes
  7. Planting trees: 54 minutes
  8. Badminton: 54 minutes
  9. Weeding: 52 minutes
  10. Hopscotch: 49 minutes
  11. Skateboarding: 48 minutes
  12. Playing with kids (vigorous): 48 minutes
  13. Golf (carrying clubs): 44 minutes
  14. Horse grooming: 40 minutes
  15. Cross-country hiking: 40 minutes
  16. Rollerblading: 35 minutes
  17. Tennis: 35 minutes
  18. Biking 12-14 mph: 30 minutes
  19. Running 10-minute mile: 24 minutes
  20. Jumping rope: 24 minutes
* Values were calculated using a list of calories burned in a 30-minute period published by the Harvard Medical School. They are based on activity for a 155-pound person.

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