high-intensity interval training

American  

[hahy-in-ten-si-tee in-ter-vuhl trey-ning] / ˈhaɪ ɪnˌtɛn sɪ ti ˈɪn tər vəl ˌtreɪ nɪŋ /

noun

1. a type of interval training for physical conditioning and fitness that uses short bursts of very intense exertion, alternating with short periods of rest or lighter exertion, to exploit the body’s systems for generating anaerobic energy. HIIT, H.I.I.T.

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Etymology

Origin of high-intensity interval training

First recorded in 1975–80

Example Sentences

See Examples For:

high-intensity interval training

His longtime business, Bootcamp H20 — fitness classes for adults held at private and public pools around L.A. — blended high-intensity interval training, circuit training, aerobics, plyometrics, strength training and endurance training.

From Los Angeles Times ● Jan. 1, 2026

In Lumin Fitness' darkened studio space in Dallas, Texas, LED screens line the walls from where AI personal trainers guide up to 14 gym goers at a time through personalised workouts or high-intensity interval training.

From BBC ● Jan. 3, 2024

They pointed to a 2021 review of more than 100 exercise studies that examined the effect on weight loss in adults of aerobic, resistance or high-intensity interval training in combination or alone.

From Scientific American ● Jul. 19, 2023

The beauty of the fartlek is that, unlike in traditional high-intensity interval training workouts, walkers or runners don’t have to glue themselves to a watch or a fitness tracker to boost their muscular endurance.

From Seattle Times ● Oct. 4, 2022

That June, Reynolds wrote her first story about single-digit high-intensity interval training, or HIIT.

From Slate ● Apr. 19, 2022