

“I Sacrificed Years of Performance by Not Eating Enough”—How Lydia O’Donnell Broke Every PB (#34)
Lydia O’Donnell is a New Zealand 10K national champion, a 20th-place finisher at the New York City Marathon and the founder of FEMMI, a running app built specifically for women. In this episode, Lydia shares how years of underfueling, overtraining and pressure to make her body smaller brought her running career close to breaking point. After losing her period and eventually landing in hospital, she began learning about female physiology, changing her relationship with food and adapting her training around what her body genuinely needed. The result was a remarkable late-20s breakthrough in which she improved her personal bests across every distance from 5K to the marathon. We explore the warning signs athletes commonly ignore, why weight loss isn’t the answer to better performance and how women can adjust training across the menstrual cycle. Lydia also explains how FEMMI personalises its running programs, why every female athlete should track her cycle, how she approaches hydration and heavy strength training, and where research into female physiology still needs to improve. Episode breakdown: 00:00 — Meet Lydia O’Donnell 00:27 — Are Most Training Plans Built for Men? 01:37 — The Coach Who Taught Her Patience 04:55 — When Did Her Progress Begin to Stall? 06:44 — “They Didn’t Know How to Coach Women” 08:30 — The Hospital Visit That Changed Everything 10:26 — What Warning Signs Did She Ignore? 14:48 — Is Your Body Asking You to Stop? 16:42 — Does Losing Weight Really Make You Faster? 19:14 — The Book That Saved Her Running Career 20:12 — Why Lydia Started Coaching Herself 23:02 — From Personal Struggle to Founding FEMI 26:43 — How Does the FEMI App Work? 28:32 — Should Training Change Across Your Cycle? 32:55 — Can AI Create Truly Personalised Training? 34:41 — The One Thing Every Female Athlete Should Track 36:16 — Are Runners Too Obsessed With Data? 37:31 — Why Lydia Once Avoided Drinking Water 39:04 — Should Runners Lift Heavy? 42:16 — Inside Lydia’s Strength Sessions 45:19 — Why Is Female Physiology So Understudied? 48:12 — Can Self-Knowledge Improve Performance? 49:02 — Where Can Women Find Credible Information? 51:37 — Giving Female Athletes a Bigger Platform This is a public episode. If you would like to discuss this with other subscribers or get access to bonus episodes, visit johngetstrong.substack.com


















