How does she run so fast? The physiological basis for the elite performance of the new—over 90 years of age—world record holder in the 200m sprint: A case report

Introduction: A91-year-old female set the W90+ world record (WRW) in the 200m sprint in May 2024, with a time of 51.47s, which was 1.48s faster than the previous record. Purpose: The aim of this study was to examine the in vivo and ex vivo physiological profile underpinning the elite performance of the 91-year-old sprinter and compare, when possible, her data to the literature. Methods: Cardiorespiratory parameters were measured during a ramp cycling test until exhaustion, and muscle oxidative capacity (mVO 2 ) measured with a repetitive intermittent arterial occlusion test via NIRS. The cross-sectional area (CSA) of the knee extensors was evaluated with panoramic ultrasound. Fatigability of the knee extensors was quantified as the reduction in power during an exercise lifting a 20% maximal voluntary isometric contraction (MVIC) load as fast as possible once every 3s for 4-min. Fiber type distribution, fiber CSA and mitochondrial function were evaluated in a vastus lateralis (VL) muscle biopsy. Results: VO 2peak was 23 ml·kg −1 ·min −1 (1.332 L·min −1 ) achieved at 98 W peak power, heart rate of 141 bpm, cardiac output of 13.6 L/min. Herk-value from the mVO 2 test was 1.83 %·s −1 . CSA at 50% femur length was 36.5 cm 2 . Knee extensor MVIC was 79 Nm, and the power reduction during the exercise was 43%. VL fiber type distribution was 38% myosin heavy chain (MyHC) I, 49% IIa, 5% I-IIa, 5% IIa-IIx and 2% IIx. Interestingly, the slow fibers (4267 ± 2181 μm 2 ) were markedly larger than the fast MyHC II fibers (2752 ± 1608 μm 2 , ratio II/I = 0.59). Mitochondrial respiratory capacity (O 2 flux) was 58 and 68 pmol·(s·mg) −1 when complex I and complex II coupled together were in state of oxidative phosphorylation and in the uncoupled condition, respectively. Conclusion: The WRW’s cardiorespiratory parameters (central components of physical fitness) were comparable to the 90 th percentile of women aged 50-59 yrs (1), while her mitochondrial function (a peripheral component of physical fitness) was indistinguishable from younger women, supporting limited changes in mitochondrial function with aging (2). Her whole muscle CSA was consistent with individuals of the same age, despite her exceptionally large type I fibers and high percentage of Type II fibers. The neuromuscular function was comparable to women in their 80s (3). We speculate that the WRW’s exceptional performance was driven, in part, by her remarkably large slow fibers, a high proportion of fast fibers, and mitochondrial function equivalent to young adults. This highlights the potential for sprint training to promote health and youthfulness, even in advanced age. References: 1. Kaminsky LA, et al. Mayo Clin Proc.2022 2. Lanza IR et al. J Physiol.2024 3. Sundberg CW et al. J Appl Physiol.2018. PRIN Trajector-AGE (2020477RW5) and ReActiveAGE (P2022FNCPR) grants to MVF and SP, and a NIH-R01 grant (AG048262) to CWS. This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.