Code to Conception

Daily micro-protocols for the 90-day miracle window

| September 25, 2025 |

🔬 Pre-Bump Biology  

HIIT isn’t automatically the fertility villain—it’s what happens when high-intensity training collides with low energy availability. Within just 5 days, an under-fueled HIIT routine can silence ovulation signals in women, while excessive cycling heat or oxidative stress can dent sperm quality. Done right, HIIT can actually improve reproductive function, especially in PCOS.

🧬 Protocol Drop  

Today’s 1-Step Protocol: 

Cap HIIT at 2 sessions/week (≤100 min total), using 1–4 min intervals at 90–95% HR_peak. Always train fed-state—take 0.5–1 g/kg carbs within 60 min pre-session, and refuel with 20–30 g protein + 1 g/kg carbs within 2 hours after. Men: keep spin under 5 h/wk and avoid hot tubs to protect sperm.

👉 Read the full study summary

📚 Glossary Pop  

Energy Availability (EA): The amount of energy left to run your body after subtracting exercise calories from food calories, divided by fat-free mass. When EA drops below ~30 kcal/kg FFM/day, the brain cuts GnRH/LH pulses—switching off ovulation in women and lowering testosterone and sperm quality in men.  

Want to learn more?

Patten, R. K., et al. (2022). High-intensity training improves reproductive outcomes in PCOS: RCT evidence. Human Reproduction, 37(5), 1018–1029. https://doi.org/10.1093/humrep/deac047 

Lo Giudice, A., et al. (2024). Physical activity and male fertility: Meta-analysis of RCTs. World Journal of Men’s Health, 42(3), 555–562. https://doi.org/10.5534/wjmh.230106 

Angelidi, A. M., et al. (2024). Relative Energy Deficiency in Sport (RED-S): Endocrine manifestations. Endocrine Reviews, 45(5), 676–700. https://doi.org/10.1210/endrev/bnae011 

Wise, L. A., et al. (2012). Physical activity and time-to-pregnancy. Fertility and Sterility, 97(5), 1136–1142.e4. https://doi.org/10.1016/j.fertnstert.2012.02.025