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News: Too Much High-Intensity Exercise May... (The New York Times) - Behind the headlines

In the news

Media coverage of health and science topics

The New York Times March 24, 2021

Too Much High-Intensity Exercise May Be Bad for Your Health (Published 2021)

by Gretchen Reynolds

A new study hints that excessive HIIT may harm your mitochondria, the energy generators found in every cell of your body.

Read more at The New York Times

Behind the headlines

Research findings and data from the National Library of Medicine

PubMed articles

Cell Metab MARCH 13, 2021

Excessive exercise training causes mitochondrial functional impairment and decreases glucose tolerance in healthy volunteers

M Flockhart et al

Exercise training positively affects metabolic health through increased mitochondrial oxidative capacity and improved glucose regulation and is the first line of treatmen …

Med Sci Sports Exerc DEC. 11, 2020

Endurance and Sprint Training Improve Glycemia and VO2peak, but only Frequent Endurance Benefits Blood Pressure and Lipidemia

HL Petrick et al

As only high-frequency END improved BP and lipid tolerance, free-living glycemic regulation was better on days which participants exercised, and favorable individual resp …

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The Scientist MARCH 23, 2021

Extreme Exercise Carries Metabolic Consequences: Study

Healthy people put through high-intensity interval training, or HIIT, displayed insulin resistance and mitochondrial dysfunction after working out excessively.

The New York Times JAN. 20, 2021

The Benefits of Moderate Exercise (Published 2021)

High-intensity workouts get a lot of attention and can be great for health. But moderate physical activity may have metabolic advantages.

The New York Times NOV. 10, 2021

Does High-Intensity Exercise Affect Our Hearts? Minds? Life Spans? Waistlines?

What you need to know about high-intensity interval training, or HIIT.

CNN News NOV. 27, 2022

Try this interval workout to avoid HIIT burnout or injuries | CNN

High-intensity interval training, or HIIT workouts, has been a top 10 fitness trend since 2014. Yet there are similar forms of interval training that may be a better fit for your training goals and needs, experts say. Here are the three variations.

The New York Times MAY 30, 2018

Hate High-Intensity Exercise? Try It. You Might Like It. (Published 2018)

Just trying a H.I.I.T. workout for the first time may be a critical step in including high-intensity training as part of your everyday routine.