"I’d like a good lunch-hour workout that I can do at my gym in 30 minutes flat, giving myself plenty of time to shower and cool down. What do you recommend?"
—BRADLEY S., TACOMA, WA
You don’t need to change the exercises you do in a typical workout, just the speed with which you do them. “When we move at top speed, we engage fast- and superfast-twitch muscles, which send a ‘fight or flight’ signal to the brain,” says Justin O’Connor, head trainer of the Under 20 Workout fitness program. “This engages the pituitary gland, which releases human growth hormones and speeds both muscle building and fat burning.”
O’Connor recommends doing a series of high-intensity, short-burst exercises (burpees, rope jumping, weights), moving your muscles at top speed for 20–30 seconds then resting for 10 seconds. “It can produce up to 10 times the calorie-burning benefits,” he says. “After 20 minutes, you’ll have time to shower, cool down, and be back at your desk.”