Relationship between increasing exercise intensity and visual function in pre-pubertal soccer players

Children performing team sports such as basketball and soccer must judge the location of their team-mates and opponents whilst participating in strenuous physical activity over long durations. Little is known on the relationship between visual function and increasing levels of exercise intensity. Therefore, the purpose of the study was to examine the relationship between visual function and increasing levels of exercise intensity in junior soccer players. Nine first team (FT) (age: 11.7 ± 0.32 years) and nine reserve team (RT) (age: 11.8 ± 0.32 years) male soccer players completed a discontinuous incremental running exercise test to exhaustion on a treadmill. Each submaximal stage (8.0, 9.7 and 10.5 km.h-1) lasted three minutes, immediately after each stage inner (10 °) and outer peripheral vision (20 °) was assessed. ANOVA analyses demonstrated no significant differences (FT: 56.4 ± 7.24 vs RT: 55.8 ± 9.76 ml.kg-1.min-1) between the groups for VO2peak. RT players had significantly lower (p<0.05) submaximal values of%VO2peak andΔ HR (pre - exercise heart rate) at all three submaximal running speeds compared to FT players. FT players had significantly greater (p<0.05) inner peripheral vision at 9.7 km.h-1 (FT: 40 ± 8 vs RT: 29 ± 19Hz) and peak exercise (FT: 42 ± 3 vs RT: 27 ± 16Hz). Significant correlations (p<0.05) were noted between outer peripheral vision and respiratory exchange ratio following maximal exercise (r = 0.55) and between respiratory rate and outer peripheral vision following the first(8.0 km.h-1) exercise stage, r = -0.49. Whilst, significant correlations do exist, the magnitude of these indicate limited relationships between visual function and cardio-respiratory variables. However, the differences in peripheral vision between the two groups may be potentially significant and warrant further investigation.