Physiological and performance adaptations to a 48-week periodized triathlon training program in elite athletes: a longitudinal study
DOI:
https://doi.org/10.15561/26649837.2026.0408Keywords:
elite athletes, periodized training, polarized training, longitudinal study, triathlonAbstract
Background and Study Aim. Triathlon is a multidisciplinary endurance sport that demands a very high level of physiological and physical capacity. Therefore, the implementation of periodization strategies and the appropriate distribution of training intensity contribute to optimizing performance adaptations in elite athletes. This study aimed to examine longitudinal physiological and performance adaptations to a 48-week polarized periodized training program in elite triathletes, with particular emphasis on the magnitude, consistency, and practical relevance of adaptations. Materials and Methods. A longitudinal quasi-experimental research design was used in this study, with repeated measurements taken at three time points: pre-intervention, mid-intervention, and post-intervention. A total of 18 elite Indonesian triathletes (8 men and 10 women) preparing for the 2025 SEA Games participated in this study. A 48-week training program was designed using a polarized training model divided into the general preparation, specific preparation, and competition phases. The variables measured included 1 km swim time, VO2max, Functional Threshold Power (FTP), and muscular endurance (push-ups and sit-ups). Data analysis was performed using repeated measures ANOVA (p < 0.05). Results. The results of the study showed a significant increase in all variables over time (p < 0.001). Swimming times improved by 5.61%, while VO2max and FTP increased by 6.64% and 9.63%, respectively. Muscular endurance capacity showed the greatest improvement, with push-ups increasing by 16.74% and sit-ups by 12.82%. All variables demonstrated a large effect size (η2 = 0.68–0.73). All participants showed positive trends; however, interpretation should consider measurement error and the absence of a control group. Conclusions. A 48-week periodized training program using a polarized intensity model is associated with improvements in swimming times, aerobic capacity, FTP, and muscular endurance in elite athletes. These findings provide applied insights for long-term training design in elite endurance athletes.References
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Copyright (c) 2026 Muchammad Fadly Arif, Oce Wiriawan, Mochamad Purnomo, Achmad Widodo, Irmantara Subagio, Afif Rusdiawan, Muhammad Labib Siena Ar Rasyid, Donny Ardy Kusuma
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