A seven-minute workout sounds too good to be true. Can you really get an effective exercise session in such a short period of time?
Answer: It depends.
“If you look at basic physiology, there is an inverse relationship between exercise duration and exercise intensity,” says Chris Jordan, director of exercise physiology at Johnson & Johnson Human Performance Institute. “If you work out harder, you can work out for less time and get similar health and fitness returns.”
And that's the catch: You need to work out hard and make every second of your workout count if you're going to do a seven-minute session.
In a 2013 study co-authored by Jordan, they recommend high-intensity circuit training. That means that on a scale of 1 to 10 with 10 being your absolute hardest, you should be working at an 8 or 9. “If you are doing high intensity, it's going to be more draining and you're going to be fatiguing a lot quicker,” says Jackie Church, an exercise physiologist and ACE certified trainer.
If you want even more of a challenge, do the workout with bands like the TheraBand CLX. “This will maximize your heart rate, burn out your muscles, and make it more effective,” Church says. “You will start to feel it after just a few reps if you add resistance.”
You want to perform exercises that work multiple large muscles, such as burpees, squats, and pushups. Doing these types of exercises with little rest in between sets is the key to getting both aerobic and strength benefits.
“A typical cardio workout might be riding on a stationary bike at a constant, moderate intensity for 45 to 60 minutes, watching TV or checking Facebook,” Jordan says. “All you can expect from that are moderate fitness improvements.”
With high-intensity circuit training, however, you get both cardiovascular benefits since it's fast-paced as well as strength benefits since you're doing resistance work. And in addition to burning calories during the workout, you'll keep burning calories and fat afterward. Research shows that high-intensity workouts increase the amount of growth hormone and catecholamines (another type of hormone) in the blood. Both of these facilitate muscle mass gain and fat metabolism.