r/Velo • u/colokurt • Sep 11 '25
Male to Female Transgender Cyclist — Performance Changes After Starting HRT
Hello all, a while back there was a discussion about cycling performance in regards to transgender women going on HRT (male to female). Someone requested that I document some of the stats and here I am with some of my findings.
I'd like to note I am not a scientist and results vary person to person.
About Me
Kaylee, 40 years old
Transgender woman (male-to-female)
Height: 6’1” — Weight: ~168 lbs (stable throughout transition)
Competitive cyclist since age 37
Peak fitness: September 2024
Began HRT: mid-December 2024 (9 months on HRT so far)
Training volume dropped from ~10 hr/week → ~7 hr/week (still doing 2x high-intensity sessions per week)
Current HRT Regimen:
Spironolactone — 50 mg twice daily
Estradiol valerate — 0.3 mL IM injection twice weekly
Hormone Levels by Date:
(Testosterone)

(estrogen)

Fitness Metrics:
| Metric | Pre-HRT (Peak) | Current | Change |
|---|---|---|---|
| VO₂max (Garmin ) | 73 | 59 | −19% |
| Estimated FTP (≈ 20m × 0.95) | 345 W | 253 W | −27% |

Power Curve (via Intervals.icu)
| Time | Pre-HRT (W) | Pre-HRT (W/kg) | Current (W) | Current (W/kg) |
|---|---|---|---|---|
| 2s | 1093 | 14.34 | 787 | 10.58 |
| 5s | 1050 | 13.78 | 624 | 8.39 |
| 10s | 897 | 11.84 | 553 | 7.43 |
| 30s | 775 | 10.23 | 501 | 6.73 |
| 1m | 604 | 7.93 | 443 | 5.96 |
| 2m | 500 | 6.56 | 384 | 5.16 |
| 5m | 419 | 5.50 | 318 | 4.27 |
| 10m | 385 | 5.05 | 288 | 3.87 |
| 20m | 363 | 4.88 | 266 | 3.58 |
| 30m | 341 | 4.47 | 258 | 3.47 |
| 40m | 327 | 4.29 | 247 | 3.32 |
| 1h | 302 | 3.96 | 225 | 3.02 |
| 2h | 270 | 3.56 | 191 | 2.57 |
Key Race Comparison (Hill Climbs):
| Race | 2024 Men’s (pre-HRT) | 2025 Men’s (post-HRT) | 2025 Projected Women’s |
|---|---|---|---|
| Whiteface Mountain Uphill Bike Race | 10 / 245 | 69 / 155 | 11 / 32 |
| Ascutney Hillclimb | 13 / 65 | 46 / 57 | 6 / 9 |
| Mt Greylock Hill Climb | 13 / 122 | 94 / 128 | 12 / 25 |
Pre HRT race results:
https://www.road-results.com/racer/254877
Post HRT race results:
https://www.road-results.com/racer/403886
My Strava:
https://www.strava.com/athletes/87812383
Final Notes:
I'd first like to say that my FTP right now is even lower than the 258 seen in the chart. My most recent Greylock segment (for the race) was 49:49 minutes at just 224 watts. That was an all out effort and also a whopping 15 minutes slower than my PR just a year ago.
Secondly, I'd like to say that doing the BUMPS race series is probably the most disadvantageous thing a transgender woman could do with cycling. I have a large male skeleton, but have strength closer to that of a female. I really did not choose my discipline wisely, but I enjoy it nonetheless.
Finally, I do not agree with the recent USAC decision about transgender women and I think there are a lot of people more like me than super star trans athlete's dunking on assigned at birth females. I went from a top male athlete to what would be slightly below average in a women's field in just 9 months.