What Happens To Visceral Fat When You Walk FASTED

Summary

Dr. Michael Diamonds presents fasted morning walking as a way to encourage the body to use more fat for fuel and improve its ability to switch between fuel sources. He explains this through three ideas:

• Insulin and fat storage: He compares insulin to a “lock” on stored fat, arguing that insulin tends to be lower after an overnight fast. Walking before breakfast may therefore increase the proportion of energy drawn from fat during the walk.
• Growth hormone: He describes growth hormone as helping mobilize stored fat and says fasting conditions may support this process. He recommends an easy pace for comfort and energy use, with brief faster intervals as an optional addition.
• Metabolic flexibility: He compares the body to a hybrid car that can switch between carbohydrates and fat. He says regular fasted walks may help the body become more efficient at using fat when carbohydrates are less available.

He also emphasizes that fasted walking does not replace a calorie deficit: overeating later can offset its effects. The benefit he describes is mainly a change in fuel use and the body’s response to food—not a guarantee of greater weight loss.

Suggested routine

• Prepare walking clothes and shoes the night before.
• Walk before breakfast, ideally soon after waking. Start with 10–15 minutes at a comfortable, conversational pace; he suggests roughly 4–5 km/h.
• Drink water beforehand. He also says a small black coffee is an option if needed.
• For an optional interval version of “Japanese walking”:
  1. Warm up with 5 minutes at a normal pace.
  2. Alternate 3 minutes briskly with 3 minutes at a normal pace.
  3. Repeat for 5–10 cycles, adjusting to the desired walk length.
• Be consistent for several weeks; the video recommends 4–6 weeks as a practical trial.
• After the walk, have breakfast with 30–40 grams of protein, according to the presenter, to help with hunger and muscle repair.
• If possible, walk outdoors in morning light. The presenter says this may help regulate the body clock and sleep timing.

The video cites research comparing exercise before and after breakfast, reporting greater fat use during exercise in the fasted group but similar overall weight loss between groups. It also references research on fasting and growth hormone, and a Belgian study on training before breakfast and fat-burning adaptations.

Presenters and sources

• Presenter: Dr. Michael Diamonds, as identified in the subtitles
• Studies or sources mentioned by the presenter:
  • A six-week randomized trial involving 32 overweight men, attributed to researchers from the Universities of Bath and Birmingham and a journal named in the subtitles as Clinical Endocrinology and Metabolism
  • A study of a two-day fast and growth hormone in healthy men; the subtitles do not provide a specific citation
  • A Belgian university study on training before breakfast; the university and publication are not named in the subtitles