Exercise for Half an Hour Three Days a Week or Go for a Two-Hour Bike Ride on the Weekend?

Everyday Health Dilemmas Solved
Better choice: Half an hour three days a week
Ideally, aim for 30 to 60 minutes of activity at least five days a week. Every time you exercise, you reap benefits like lowering blood sugar and boosting metabolism.
But... For weight loss, you can burn just as many calories in one shot as you might spread over the week. You're still better off exercising than sitting on the couch. If possible, spread the activity out over two days, and warm up first.

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