Author(s): COSIO, P., MORENO-SIMONET, L., PADULLES, X., PADULLES, J.M., CADEFAU, J.A., Institution: NATIONAL INSTITUTE OF PHYSICAL EDUCATION OF CATALONIA (INEFC), Country: SPAIN, Abstract-ID: 1387

INTRODUCTION:
Exercise-induced muscle damage reflects overlapping mechanisms that evolve with distinct time courses across symptomatic and molecular recovery processes [1,2]. Single biomarkers rarely capture this multidimensional response [3], limiting recovery interpretation when comparing exposures. However, the integrated biomarker response (IBRv2) provides a standardized way to combine multidomain signals into a single recovery index [4,5]. Therefore, the purpose of the research was to compare hamstring muscle damage after different exercise exposures using the IBRv2 approach to holistically assess muscle recovery dynamics.

METHODS:
Healthy and physically active youth participated in three exercises exposures: (i) repeated-sprint training (RST), consisting of 10-repeated 40-meter sprints [15 males, 14 females]; (ii) Flywheel Russian belt Deadlift (FRBD) training session, consisting of 5 sets x 10 repetitions [15 males, 15 females]; and (iii) football match (FM): a 90-minute football match [19 males]. Isometric hamstring peak force and perceived soreness, through the 90ºhip:20ºknee test, together with serum biomarkers of structural (creatine kinase [CK], sarcomeric mitochondrial CK [sMtCK]), and oxidative damage (malondialdehyde [MDA], oxidative stress index [OSI], were assessed at baseline and 24, 48 and 72 hours post-exercise. The IBRv2 approach was computed to examine muscle recovery across exercise exposures. Briefly, the steps were: (1) data log-transformation; (2) Z-scoring; (3) calculating individual biomarkers variation; and (4) sum of individual biomarkers variation, IBRv2 index [4,5]. Two-way mixed ANOVA [time (pre, 24h, 48h, 72h) x exposure (RST, FRBD, FM)] were conducted to identify exposure-specific IBRv2 responses.

RESULTS:
All exposures increased IBRv2 during the 72-hour recovery period [F(3,225) = 402.1, p < 0.001]. Further, a significant time-exposure interaction revealed that FM and FRBD elicited higher IBRv2 than RST [F(6,225) = 5.4, p < 0.001]. However, domain-based analyses showed that FM elicited a greater structural biomarker response [F(2,75) = 5.6, p = 0.006], whereas FRBD elicited a more pronounced effect in the neuromuscular biomarkers domain [F(2,75) = 9.1, p < 0.001].

CONCLUSION:
Hamstring muscles require more than 72 hours to recover across exercise exposures. The IBRv2 approach may help practitioners plan recovery strategies according to the predominant affected domain after specific hamstring-damaging exercises.

REFERENCES:
[1] Bestwick-Stevenson et al., (2022), Int J Sports Med, https://doi.org/10.1055/a-1834-7177
[2] Bellosta-López et al., (2024), J Sci Med Sport, https://doi.org/10.1016/j.jsams.2024.04.002
[3] Deyhle et al., (2024), Med Sci Sports Exerc, https://doi.org/10.1249/MSS.0000000000003399
[4] Sanchez et al., (2013), Environ Sci Pollut Res Int, https://doi.org/10.1007/s11356-012-1359-1
[5] Mattos et al., (2024), Environ Sci Pollut Res Int, https://doi.org/10.1007/s11356-023-31255-4