The aim of this study is to monitor short-term seasonal development of young
Olympic weightlifters’ anthropometry, body composition, physical fitness, and sport-specific
performance. Fifteen male weightlifters aged 13.2 1.3 years participated in this study. Tests
for the assessment of anthropometry (e.g., body-height, body-mass), body-composition (e.g.,
lean-body-mass, relative fat-mass), muscle strength (grip-strength), jump performance (drop-jump
(DJ) height, countermovement-jump (CMJ) height, DJ contact time, DJ reactive-strength-index (RSI)),
dynamic balance (Y-balance-test), and sport-specific performance (i.e., snatch and clean-and-jerk)
were conducted at different time-points (i.e., T1 (baseline), T2 (9 weeks), T3 (20 weeks)). Strength tests
(i.e., grip strength, clean-and-jerk and snatch) and training volume were normalized to body mass.
Results showed small-to-large increases in body-height, body-mass, lean-body-mass, and lower-limbs
lean-mass from T1-to-T2 and T2-to-T3 (D0.7–6.7%; 0.1 d 1.2). For fat-mass, a significant small-sized
decrease was found from T1-to-T2 (D13.1%; d = 0.4) and a significant increase from T2-to-T3 (D9.1%;
d = 0.3). A significant main effect of time was observed for DJ contact time (d = 1.3) with a trend
toward a significant decrease from T1-to-T2 (D–15.3%; d = 0.66; p = 0.06). For RSI, significant small
increases from T1-to-T2 (D9.9%, d = 0.5) were noted. Additionally, a significant main effect of time was
found for snatch (d = 2.7) and clean-and-jerk (d = 3.1) with significant small-to-moderate increases
for both tests from T1-to-T2 and T2-to-T3 (D4.6–11.3%, d = 0.33 to 0.64). The other tests did not
change significantly over time (0.1 d 0.8). Results showed significantly higher training volume for
sport-specific training during the second period compared with the first period (d = 2.2). Five months
of Olympic weightlifting contributed to significant changes in anthropometry, body-composition,
and sport-specific performance. However, hardly any significant gains were observed for measures
of physical fitness. Coaches are advised to design training programs that target a variety of fitness
components to lay an appropriate foundation for later performance as an elite athlete
