Run More Hills
One benefit of treadmills: You can run uphill without having to run back down. “We know that it’s downhill running that typically causes soreness and impact injuries in the calf and knee,” says Pierce. With treadmill runs, do repeats that are easier on your joints by going for an uphill push and flattening for recovery.
Ditch the programmed “Fat Burn” setting
Don’t be fooled by the “fat burn” button. The lower intensity just means that a higher percentage of your caloric expenditure is from fat. You’re still always going to burn more fat running faster than you are running slower. For example: Pierce says if you run 10 mph and 60% of your energy comes from fat calories, you might burn 100 calories per mile. But if you run 6 mph and 40% of your energy comes from fat, you may burn 300 calories per mile. Basically: ramp up your speed, and your fat burn doubles.
Skip the weights
Adding in weighs could do more than help you put on the muscle; it could put you off balance. “Weights can change your biomechanics and the point of impact, which leads to injury,” says Pierce. Save your strength training for a later workout.