High-Intensity Interval Training, as the name suggests is a workout where you do intense exercise alternated with low-intensity recovery periods. From improving muscle mass to aiding weight loss, the workout claims to have many benefits. But a new study has found a shocking drawback of performing the exercise too often.
The study
As per new research, too much high-intensity interval training every week can backfire, instead of improving your health.
While a moderate amount of HIIT can improve endurance, long hours of it can overstress the body and dampen your metabolism, says a small study published on March 18 in Cell Metabolism.
Analysis
For the study, researchers from the Swedish School of Sport and Health Sciences recruited 11 healthy adult volunteers (6 females and five males) for regular HIIT sessions on an exercise bike. All the participants completed short intervals of all-out-effort pedalling, with short periods of rest and gradually increased the time they spent working out.
The results
The study found that moderate HIIT workouts improved exercise performance, but long HIIT workouts every day deteriorate the health of the participants.
This means, HIIT does have benefits but too much of it can stress out the body and decrease your performance.
For how long you should do HIIT in a week?
HIIT has a positive impact when done for up to 90 minutes a week. It can improve athleticism and overall health. Short intense workouts with little rest in between (also called Tabata) are the best
Overdoing HIIT
The researchers in the study also looked at how much exercise is too much exercise. They found that problems started when participants began working out nearly every day for a longer duration and with more energy. In total, these participants were doing 152 minutes of intense exercise each week.
At this point, they stopped improving on the bike. Tests results showed that they had worse metabolic health during the most intense period of training and less stable blood sugar levels and mitochondrial dysfunction.
These people also showed markers of oxidative stress, which is a type of cell damage linked with long term health risks like chronic illness and premature ageing, as well as short term symptoms like fatigue and inflammation.
The good news is that the participants were able to recover after a week of less frequent exercise and their performance also improved. Though their mitochondria weren’t still working well as before the overtraining.
Verdict
The study doesn’t encourage you to stop opting for HIIT but rather pursue moderation, which gives you time to recover. If you are new to exercising, you especially need to be careful.
