Q

What constitutes 'high intensity' in HIIT?

From 5 years of verified research · Vassili Sandqvist
A

High intensity in HIIT means reaching 85–95% of your maximum heart rate during work intervals. It's not just about feeling tired; it’s about sustaining near-maximal exertion for short bursts, typically 20-40 seconds, where continuing becomes mechanically impossible.

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