Biophysical impact of five-weeks training cessation on sprint swimming performance Ruiz Navarro, Jesús Juan Gay Párraga, Ana Zacca, Rodrigo Cuenca Fernández, Francisco López Belmonte, Óscar Morales Ortiz, Esther López Contreras, Gracia exercise physiology oxygen uptake kinetics energetic, biomechanics, detraining Purpose: To assess changes in swimming performance, anthropometrics, kinematics, energetics, and strength after 5-week training cessation. Methods: Twenty-one trained and highly trained swimmers (13 males: 17.4 [3.1] y; 50-m front crawl 463 [77] FINA points; 8 females: 16.7 [1.7] y; 50-m front crawl 535 [48] FINA points) performed a 50-m front-crawl all-out swim test, dryland and pool-based strength tests, and 10-, 15-, 20-, and 25-m front-crawl all-out efforts for anaerobic critical velocity assessment before and after a 5-week training cessation. Heart rate and oxygen uptake ( ˙VO2) were continuously measured before and after the 50-m swim test (off-kinetics). Results: Performance was impaired 1.9% (0.54 s) for males (P = .007, d = 0.91) and 2.9% (0.89 s) for females (P = .033, d = 0.93). Neither the anthropometrical changes (males: r2 = .516, P = .077; females: r2 = .096, P = .930) nor the physical activities that each participant performed during the off-season (males: r2 = .060, P = .900; females: r2 = .250, P = .734) attenuated performance impairments. Stroke rate and clean swimming speed decreased (P < .05), despite similar stroke length and stroke index (P > .05). Blood lactate concentrations remained similar (P > .05), but VO˙ 2 peak decreased in females (P = .04, d = 0.85). Both sexes showed higher heart rate before and after the 50-m swim test after 5 weeks (P < .05). Anaerobic metabolic power deterioration was only observed in males (P = .035, d = 0.65). Lower in-water force during tethered swimming at zero speed was observed in males (P = .033, d = 0.69). Regarding dryland strength, lower-body impairments were observed for males, while females showed upper-body impairments (P < .05). Conclusions: A 5-week training cessation yielded higher heart rate in the 50-m front crawl, anaerobic pathways, and dryland strength impairments. Coaches should find alternatives to minimize detraining effects during the off-season. 2025-01-23T10:35:23Z 2025-01-23T10:35:23Z 2022-07-21 journal article Ruiz-Navarro, J. J., Gay, A., Zacca, R., Cuenca-Fernández, F., López-Belmonte, Ó., Lopez-Contreras, G., ... & Arellano, R. (2022). Biophysical impact of 5-week training cessation on sprint swimming performance. International journal of sports physiology and performance, 17(10), 1463-1472. https://hdl.handle.net/10481/100121 10.1123/ijspp.2022-0045 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional