Refeeds

This content is for informational purposes only and does not constitute medical or nutritional advice. Speak with your health professional before starting this protocol.


Note: Refeed timing and carbohydrate targets are fixed by your sprint level. Do not modify refeed parameters based on how you feel — the schedule is set at sprint setup and does not change. If you feel unwell during or after a refeed, stop and consult your health professional.

A refeed is a planned, structured increase in calories, primarily from carbohydrates, for one full day. It is a built-in part of the Fat Loss Sprint protocol. It is not a reward, not a cheat day, and not a deviation from the plan. It is a strategic metabolic tool with a specific physiological purpose.

Every sprint includes exactly two refeeds. Both are scheduled in advance by your sprint level. You cannot earn them early or delay them. They happen on fixed days.


What a Refeed Is and Is Not

A refeed is:

  • A planned 1-day increase in calories to approximately maintenance level
  • Predominantly carbohydrate-based (carbs increase significantly; protein stays the same; fat stays the same as sprint days)
  • Designed to acutely restore leptin, support thyroid function, replenish glycogen, and provide anabolic signaling
  • Part of the protocol

A refeed is not:

  • A cheat day or a cheat meal
  • Unlimited eating of whatever sounds appealing
  • A psychological reward for compliance
  • A full diet break (which is a longer, separate intervention)

Why Refeeds Are in the Protocol

Leptin Restoration

Leptin is the hormone produced by fat tissue that signals energy sufficiency to the brain. During caloric restriction, leptin drops rapidly, often faster than body fat actually decreases. This leptin decline drives many of the adaptive responses you want to avoid: increased hunger, reduced spontaneous movement, lower thyroid activity, and suppressed hormones.

Carbohydrate intake is a potent acute stimulus for leptin production. Dirlewanger et al. (2000) demonstrated that carbohydrate overfeeding increased 24-hour energy expenditure by approximately 7% and plasma leptin by approximately 28%. Even a single high-carbohydrate day produces a meaningful acute leptin response, partially countering the adaptive suppression.

Fat overfeeding does not produce the same leptin response. This is why refeeds are carbohydrate-based, not fat-based.

Thyroid Function Support

The conversion of T4 (inactive thyroid hormone) to T3 (active thyroid hormone) depends partly on carbohydrate availability. During sustained low-carbohydrate restriction, this conversion slows, contributing to metabolic rate reduction. Carbohydrate refeeds acutely stimulate T4-to-T3 conversion, partially restoring thyroid-mediated metabolic activity (Danforth et al., 1979).

Glycogen Restoration

Muscle and liver glycogen are depleted during your sprint. This depletion supports fat oxidation during the restriction phase. Periodic partial glycogen restoration through refeeding delivers:

  • Improved resistance training performance on and immediately after the refeed day
  • Muscle cell volumization (glycogen stores with water, producing a "full" look and potential anabolic signaling)
  • Relief from the flat, depleted physical feeling associated with glycogen depletion

Anabolic Signaling

Carbohydrates stimulate insulin secretion. Insulin has a permissive role in muscle protein synthesis: it does not trigger MPS directly, but adequate insulin availability enhances the MPS response to protein intake. The insulin rise from a carbohydrate refeed, combined with your ongoing protein intake, creates a temporary anabolic environment that supports lean mass preservation (Abdulla et al., 2016).

Adherence

Knowing a structured increase in eating is scheduled provides a real psychological anchor during restriction days. The refeed breaks the monotony of the sprint without disrupting progress. Plan it, look forward to it, and use it.


Your Refeed Schedule

Every sprint has exactly two refeeds, at fixed days determined by your sprint level.

FLS Sprint LevelMid-Program RefeedFinal Day Refeed
1 — LeanDay 7Day 14
2 — ModerateDay 10Day 21
3 — OverweightDay 14Day 28

These days do not shift based on how you are feeling or how the sprint is going. The mid-program refeed delivers a metabolic reset at the halfway point. The final day refeed closes the sprint and transitions you into the diet break.


Carbohydrate Targets on Refeed Days

Carbohydrates are the primary variable that changes on a refeed day. Both your mid-program and final day refeed use the same carbohydrate targets, set by your sprint level and calculated from your LBM:

FLS Sprint LevelRefeed Carbs
1 — Lean7 g/kg LBM
2 — Moderate5 g/kg LBM
3 — Overweight3 g/kg LBM

Worked examples:

  • Sprint Level 1, 70 kg LBM: 7 × 70 = 490 g carbohydrates
  • Sprint Level 2, 51 kg LBM: 5 × 51 = 255 g carbohydrates
  • Sprint Level 3, 65 kg LBM: 3 × 65 = 195 g carbohydrates

Macronutrient Structure on Refeed Days

MacronutrientRefeed Day
ProteinSame as your regular sprint days — the protocol keeps this unchanged
CarbohydratesYour sprint level target (g/kg LBM)
FatSame as your regular sprint days — the protocol keeps this unchanged

Your fat stays consistent across sprint days and refeed days. The FLS protocol already keeps fat at the minimum required for essential fatty acids and fat-soluble vitamin absorption. Reducing it further would compromise these functions with no meaningful additional benefit. More importantly, keeping fat at its lower bound reduces the risk of fat storage on refeed days, since the combination of high insulin and high dietary fat is what drives fat gain during overfeeding.

The lever on a refeed day is carbohydrates. That is the only variable that changes.


What to Eat on Refeed Days

Focus on complex, nutrient-dense carbohydrate sources. Keep fat where it is. Keep protein where it is.

Recommended carbohydrate sources: White or brown rice, potatoes, sweet potatoes, oats, pasta, bread, fruit, rice cakes, low-fat cereal.

Acceptable: Low-fat baked goods, honey, jam, low-fat dairy.

Avoid: High-fat foods — fried foods, pastries, pizza, ice cream, fast food. These combine high carbohydrates with high fat, which is precisely the combination that maximizes fat storage.

Sample Refeed Day (Sprint Level 2 Female, 51 kg LBM, Refeed Carbs = 255 g)

MealExample FoodsApprox. Macros
Meal 180 g oats, 1 banana, 1 scoop whey protein, honeyP: 35g, C: 80g, F: 6g
Meal 2150 g chicken breast, 250 g white rice, steamed vegetablesP: 48g, C: 90g, F: 6g
Meal 3150 g white fish, 200 g sweet potato, large saladP: 35g, C: 55g, F: 4g
Meal 4150 g 0% Greek yogurt, 150 g mixed berries, 1 rice cakeP: 20g, C: 30g, F: 1g
TotalP: 138g, C: 255g, F: 17g (~1,713 kcal)

What to Expect After a Refeed

The Scale Will Go Up

Expect a temporary increase of 1–3 kg on the scale the day after your refeed. This is water and glycogen, not fat. Glycogen is stored with 3–4 g of water per gram. That water shows on the scale.

This weight will dissipate within 2–3 days of resuming your sprint. Do not panic at the number. The scale going up after a refeed is expected, temporary, and a sign the refeed worked.

Training Performance Improves

Resistance training performance typically improves during and immediately after a refeed, with glycogen availability supporting higher-intensity work. Many people schedule their most demanding training session on the refeed day or the day after.

Mood and Energy Recover

Most people report significantly improved mood, energy, and motivation during and after a refeed. This is part of what makes it a useful adherence tool, not just a metabolic one.


Key Takeaways

  • A refeed is a structured, planned 1-day increase in calories from carbohydrates. It is not a cheat day.
  • The physiological purpose: restore leptin acutely, support thyroid function, replenish glycogen, and provide anabolic signaling.
  • Every sprint has exactly two refeeds: one mid-program and one on the final day. Days are fixed by sprint level.
  • Refeed schedule: Level 1 — Day 7 + Day 14. Level 2 — Day 10 + Day 21. Level 3 — Day 14 + Day 28.
  • Carbohydrate targets: Level 1 — 7 g/kg LBM. Level 2 — 5 g/kg LBM. Level 3 — 3 g/kg LBM. Both refeeds use the same targets.
  • Protein and fat stay the same as your regular sprint days. Carbohydrates are the only variable that changes.
  • Post-refeed scale increases of 1–3 kg are expected, temporary, and not fat gain.

References

Abdulla, H., Smith, K., Atherton, P. J., & Idris, I. (2016). Diabetologia, 59(1), 44–55. https://doi.org/10.1007/s00125-015-3751-0

Danforth, E., et al. (1979). The Journal of Clinical Investigation, 64(5), 1336–1347. https://doi.org/10.1172/JCI109590

Dirlewanger, M., et al. (2000). International Journal of Obesity, 24(11), 1413–1418. https://doi.org/10.1038/sj.ijo.0801395

Rosenbaum, M., & Leibel, R. L. (2010). International Journal of Obesity, 34(S1), S47–S55. https://doi.org/10.1038/ijo.2010.184