# 064 Is time under tension important for muscle growth? Page: https://stenobird.com/podcast/hypertrophy-past-and-present-7348739/064-is-time-under-tension-important-for-muscle-growth Text version: https://stenobird.com/podcast/hypertrophy-past-and-present-7348739/064-is-time-under-tension-important-for-muscle-growth.md Podcast: [Hypertrophy Past and Present](https://stenobird.com/podcast/hypertrophy-past-and-present-7348739) Published: 2026-08-11T07:44:49+00:00 Episode link: https://share.transistor.fm/s/e0c9c8af Audio file: https://media.transistor.fm/e0c9c8af/54117c2d.mp3 Processing state: not_requested JSON: https://stenobird.com/v1/public/podcasts/hypertrophy-past-and-present-7348739/episodes/064-is-time-under-tension-important-for-muscle-growth Duration seconds: 3960 ## Resource In this episode of Hypertrophy Past & Present, Jake and Chris begin with Reg Park’s 1949 pre-contest routine, which involved training six days per week, twice per day, including the infamous 20-rep breathing squat. This leads into a deep dive on time under tension: Does making a set last longer actually increase muscle growth? Jake and Chris explore why total time under tension may be the wrong thing to measure and whether we should instead be thinking about “time under stimulating tension.” Key topics include: Reg Park’s 1949 twice-a-day, six-day-per-week routine Why total time under tension may be a misleading measure of stimulus The difference between time under tension and time under stimulating tension Why the early repetitions of a high-rep set may contribute little to muscle growth Whether slowing down the concentric can maintain stimulus with fewer repetitions Why very slow eccentrics may actually reduce the hypertrophy stimulus Whether the final repetition of a set is really the most stimulating Using isometrics to replicate the stimulus of a conventional set Join our Hypertrophy Past and Present Training group on TrainHeroic.com ## Actions - request_transcript: `POST https://stenobird.com/v1/public/podcasts/hypertrophy-past-and-present-7348739/episodes/064-is-time-under-tension-important-for-muscle-growth/transcription-requests` — Idempotently request low-priority transcript generation for this episode. - read_markdown: `GET https://stenobird.com/podcast/hypertrophy-past-and-present-7348739/064-is-time-under-tension-important-for-muscle-growth.md` — Read the agent-friendly Markdown representation of this episode resource. A page view does not enqueue transcription. Agents should invoke `request_transcript` explicitly when they need this episode processed. ## Transcript Full transcripts are not published on public pages unless there is a clear rights basis.