Two-Year Longitudinal Changes in Training Level Among Male Beach Handball Athletes of the Vietnamese National Team

Background: Following the establishment of a 29-criterion assessment battery for training level in male beach handball, longitudinal monitoring of training-induced adaptation remains scarce in Asian sports science literature. Objective: This study evaluated changes in training level among Vietnamese male national beach handball athletes across three measurement points—baseline (B), after one year (L1), and after two years (L2)—spanning morphological, physiological-biochemical, psychological, physical, and technical domains. 

Methods: Fourteen male national team athletes (12 court players, 2 goalkeepers) training at the Ho Chi Minh City Sports Training and Competition Center were assessed using paired comparisons (B–L1, L1–L2, B–L2), growth rate (W%), and paired-sample t-tests. 

Main Findings: Morphological indices (height, body mass, BMI, arm span, hand span) showed no statistically significant change (p > 0.05), reflecting biological stability in mature athletes. In contrast, physiological-biochemical markers improved markedly, with VO₂max increasing by 8.75% and cardiac function index (HW) decreasing by 39.02% over the full cycle. Psychological reflex measures improved significantly (p < 0>

Conclusion: A structured two-year training program produced comprehensive, statistically significant adaptation across physiological, psychological, physical, and technical domains, while morphology remained a stable foundation, validating the sensitivity of the 29-criterion assessment framework for longitudinal athlete monitoring.