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The effect of fasting on lean muscle mass (AMA #2) — Whalespan

Content›Video›The effect of fasting on lea…

The effect of fasting on lean muscle mass (AMA #2)

Peter Attia6m · 2020-01-24

Claims Made

9

Claims Supported

3

Support Rate

33%

Support rate

3 of 9 claims supported

3 supported6 partial / not

Claims from this content

8

✕Not SupportedLonger fasting durations, such as 7-day water-only fasts quarterly or 3-day fasts monthly, may lead to significant muscle mass loss that is difficult to regain.◐Partially SupportedPeter Attia feels as strong but fatigues sooner and requires longer recovery between sets by day 3-4 of water-only fasting.✓Well SupportedWeight-bearing exercise is the most effective method for preserving or adding lean mass, followed by protein intake.◐Partially SupportedPeter Attia experienced a reduction in power output on a bicycle by at least 60-80 watts relative to his former self.Partially Supported

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Attia walks back the clinic protocol: too aggressive for healthy adults

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A. Volkovreader

4h

Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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N. Park

2d

Would love a "what would change this verdict" RSS feed. Sign me up if it exists.

◐

Resistance exercise is important during fasting to maintain mTORC1 activity in muscle.

◐Partially SupportedCycling requires more muscle contractions than strength training exercises like squats, rows, or deadlifts, which demand more of the sarcomere per contraction.

◐Partially SupportedReducing the intensity of each zone by one level may be a strategy to maintain capacity in high-intensity interval training.

?Limited ResearchExercising during a week-long fast may lead to greater lean tissue loss compared to not exercising.