Are Those 7-Minute Workouts Worth It?

7-Minute Workout on the Fitbit Blaze
7-Minute Workout on the Fitbit Blaze

7-minute workouts are found on a number of fitness trackers such as Fitbit and many fitness apps but I’ve always wondered if they were worth doing.  What good could working out for such a short period of time do for those trying to lose or maintain weight?  It turns out they do a lot.

My main exercises have always involved low-intensity, long cardio workouts (30-50 minutes).  I’ve always enjoyed doing them over high intensity interval training routines.  For one, they are easy on my joints and muscles and two, I enjoy the psychological benefits of listening to music while walking or running.  So, no I’m not giving up my evening walks or bike rides, and this study doesn’t suggest that you should; however, to boost your metabolism you might not want to skip out on those short HIIT workouts.  They really are effective at burning burning calories long after the exercise is over.

In the study, “Post Exercise Metabolic Rate Following a 6 Minute High Intensity Interval Workout” conducted by Azusa Pacific Univeristy’s Department of Physical Therapy (Petrofsky et al 2011) published in The Journal of Applied Research, post metabolic rate was significantly increased in participants of the study for several hours post-exercise.

In this study, 10 participants were placed in a controlled environment in which, other than the 6-minute workout used in the study, they remained sedentary the rest of the time.  Their diets were also controlled and consisted of the same meals.

The 6-minute workout consisted of 1 minute of warm up and 4 minutes of HIIT exercises including 8 intervals lasting 20 seconds each, followed by 10 second resting periods.  The HIIT exercisces included squats, jumping in place, lunges, split jumps, and stretching.  1 minute of cool down ended the workout.

Oxygen consumption was measured in each individual immediately before, during, and 48 hours after the 6-minute workout.

The average amount of calories burned during the 6-minute workout was 63.2 calories but the workout caused a change in metabolism that lasted well beyond the 6 minutes.  Even 24 hours later an increase in metabolism was observed.

An increased amount of calories were being burned above basil metabolic rate for several hours.  While the average calorie burn for the 6-minute workout was only 63.2 calories, the calories burned after the workout jumped to a total of 360 calories!  I’d have to walk on the treadmill a long, long time to burn 360 calories.

How do short high intensity interval workouts burn so much more than cardio exercises performed for much longer period of time?  It’s mostly due to the fact that muscles are worked harder during HIIT workouts and have a larger oxygen debt afterwards.  Muscles need to repair themselves after being worked hard and that requires energy.  The energy needed to repair the muscles, or restore oxygen levels in them, burns more calories.

During a low-intensity workout, muscles aren’t being used in way that work them hard, so post-workout calorie burn is less.  Essentially, your metabolism doesn’t change that much after a cardio workout but it does after those high intensity workouts.

So, should we just ditch the cardio workouts and only do those short HIIT routines?  Probably not for the same reasons why I enjoy working out for longer periods of time during my low-intensity workouts.

In a study on overweight women the physcho-physiological responses were considered in women participating in high intensity circuit training workouts and low intensity workouts. (Sperlich et al 2017) One of the takeaways from the findings is that there’s a psychological benefit to low intensity workouts, as well as physiological benefits.

Those both are important to consider in a person’s overall well-being.  Plus, people are more likely to stick with workouts that they enjoy over ones that are more difficult to do, even if they’re done for a shorter period of time.

To put it simply, the women in the study enjoyed the low intensity workouts more because they were less physically painful to perform.

Most of us don’t like to do things that cause pain, even if there are benefits.

Still, I will be working in those short HIIT workouts because of their  benefits.  Beyond the fact that HIIT exercises increase metabolism, they also help build muscle and strength.  I never knew how out of shape I was until I had to do yoga for a college class.  Yeah, I really had to do yoga for college!

I could last an hour on the treadmill or bike but I felt like I was going to drop dead on the yoga mat after doing lunges and planks for just a few minutes.

I wasn’t nearly as strong or physically fit as I thought I was.

The point is, is that we probably need to incorporate both high and low intensity exercises into our weekly workout schedules.  Both are highly beneficial.  And if you want to boost your metabolism, that 7-minute workout might be what you need.

References

Petrofky J, Laymon M, Altenbernt L, Buffum A, Gonzales K, Guito C. 2011. Post Exercise Basil Metabolic Rate Following a 6 Minute High Intensity Interval Workout .Journal of Applied Research [accessed 2018 Apr 4]; 11. http://mail.jrnlappliedresearch.com/articles/Vol11Iss2/Petrofsky1.pdf

Sperlich B, Wallmann-Sperlich B, Zinner C, Von Stauffenberg V, Losert H, Holmberg H-C. 2017. Functional High-Intensity Circuit Training Improves Body Composition, Peak Oxygen Uptake, Strength, and Alters Certain Dimensions of Quality of Life in Overweight Women.Front. in Physiology [accessed 2018 Apr 4]; https://doi.org/10.3389/fphys.2017.00172