I once believed exercise is necessarily just prolonged self-torture. I dreaded spending over an hour at the gym, which turned me into a yo-yo exerciser. For brief periods, I'd manage to find both the motivation and time in my schedule, only to fall off the wagon when my days got too busy.
But then I discovered that many top athletes exercise 20 minutes or less each workout. It turns out many of the benefits from exercise come from a precious few seconds of exhaustion, which triggers the body to build muscle in preparation for future strenuous activity.
A clever group of fitness researchers at the Human Performance Institute designed a circuit training routine that brings exhaustion to most major muscle groups in 7 minutes flat. The published results of the so-called "Scientific 7-minute workout" went viral: now, even the New York Times and the Pebble smartwatch have apps for users eager for a convenient way to incorporate it into their routines.
The key to high-intensity burst workouts is to strike that delicate balance between collapse-to-the-floor exhaustion and a pleasant sweat. If I train too easy, my body won't think it needs to make physiological improvements; If I work too hard in the beginning, I won't be able to finish all of the movements.
The key to exercising quickly is to get your heart rate right
"In my opinion, and broadly speaking, exercise intensity must be relatively high in order to gain cardiovascular conditioning from brief, interval style workouts," Martin Gibola, a short exercise-enthusiast and McMaster's Professor, wrote in an email. "That is essentially the trade-off for the reduced time commitment involved. While there is no hard and fast rule, average heart rate during the intervals should be at least ~80-85 percent of maximum."
This is where technology plays a vital role: training at the very specific 80 percent of maximum heart rate is difficult to do. (Maximum heart rate is more obvious, at least for anyone who's ever run until their knees buckled.) If I rely on solely on my intuition, the incentive to take it easy overrides my sense of intensity.
Getting accurate data is important, but carrying a professional grade chest strap everywhere is a real pain in the neck. Fortunately, two new wearables, the Basis Peak and the Microsoft Band, promise to track my heart rate in real time.
Previously, popular health trackers only did resting heart rate (sub-130 bpm). The only non-chest strap alternative was the Mio Alpha watch — but it wasn't meant to be worn all day, so I still had to remember to carry some extra device on me.
To test out how well each of the new 24/7 wearables could handle short-burst workouts, I wore 4 devices during my workout and checked my heart rate during each minute. The baseline is the chest strap: the closer each gets to a Polar H7, a professional-grade device, the more accurate.
The scientific 7-minute workout is twelve exercises, thirty seconds each, ten seconds of rest between: jumping jacks, wall sit, pushups, crunches, step-up onto chair, squats, tricep dips on chair, plank hold, high-knee runs, lunges, pushup one-handed hold, side plank. (Since it was designed for beginners, I increased the intensity of each workout to include a jump.)
Minute One, Jumping jacks: I feel like I could do this forever, and begin seriously question whether the 7-minute "workout" is even doing anything for me. I look down at my watch, and see only 144 beats per minute (and I should be at least 160). I crank jumping jacks into high gear to spike my heart rate.
Minute two, jumping push-ups: I finally hit 167 bpm and am feeling a good stride. Now it feels like a workout! I bang through a dozen pushups without a rest. I got this.
Minute three, jumping on onto chair: my optimism fades as I barely squeak through without stopping to rest. My effort slightly dips to 165 bpm; it's already noticeably harder to sustain the same level of effort.
Minute four, tricep chair dips: I hit my runners’ high. Embracing the pain, I burn through dips as fast as gravity will allow. 172 bpm. Did I overdo it? Eh, probably not.
Minute 5, stationary high knee running: I definitely over did. Why did I over do it!? I get through half the 30-second sprint before slowing to a crawl. Thankfully, I'm at 170 bpm and realize I can slow down a bit as I edge toward the finish.
Minute 6, jumping lunges: I get a second runners high, fueled by nothing but the optimism that I'm going to make through. I clock in at 173 dpm. I'm way overdoing it; I don't care. I will beat this damn workout! I will own it!
Minute 7, holding one-arm side plank: I realize how long seven minutes of pain can seem. I push as hard as I can to maintain good form, barely holding myself up from falling. As the time buzzes, I collapse to the ground. I made it.
It is here, on the floor, covered in sweat, that I realize 7 minutes can, indeed, be workout. My heart rate proves that.
Throughout the workout, the Microsoft Band was consistently closest to the chest strap, though it did occasionally vary in a big way. And not only does it record exercise-grade heart rate with impressive accuracy, it also has a function to automatically count reps. I could program my own version of the 7-minute workout and know whether I was improving over time, by seeing if I could perform more reps during each workout in the future. As such, it it now my default fitness band.
|Polar chest strap||Microsoft Band||Basis Peak||Mio Alpha|
The Basis Peak was near-useless; only toward the end did it register anything even close to the chest strap. It also updates with a 10 second lag, which seems like a major oversight in engineering, as it severely limits the use cases for Basis Peak. The Basis team tells me that the heart rate monitor is really only good for steady-state exercises, like a light run or bike ride, and that seems right. The watch won't help anyone who goes to the gym or a spin class.
Exercise doesn't have to be marathon of self-torture. It can be a sprint of self-torture. It's possible to get most of the mental and physical benefits of exercise from short-burst workouts. And the most delightful benefit of a brief workout is that it can be done anywhere: in the airport, in the office, anywhere you can find a spacious corner when days get too busy.
Fortunately, the next wave of fitness devices is helping aspiring health-nuts perform these workouts anywhere they happen to find a short break. The Microsoft Band is my new favorite fitness device, because it can measure both exercise-grade heart rate with impressive accuracy and it can automatically count reps.
Getting in one's daily exercise is as simple as putting on a tracker and performing the scientific 7-minute workout instead of watching cat videos on YouTube. Or, better yet, watching cat videos and working out at the same time.
Photography by Josh Lowensohn