Do Impairments in Visual Functions Affect Skiing Performance?

Abstract

Nordic and alpine skiing-related visual tasks such as identifying hill contours, slope characteristics, and snow conditions increase demands on contrast processing and other visual functions. Prospective observational studies were conducted to assess the relationships between skiing performance and a broad range of visual functions in nordic and alpine skiers with vision impairments. The study hypothesized that contrast sensitivity (CS), visual acuity (VA), and visual field (VF) would be predictive of skiing performance. Binocular static VA, CS, light sensitivity, glare sensitivity, glare recovery, dynamic VA, translational and radial motion perception, and VF were assessed in elite Para nordic (n = 26) and Para alpine (n = 15) skiers. Skiing performance was assessed based on skiers’ raw race times. Performance on the visual function tests was compared with skiing performances using Kendall’s correlations (with and without Bonferroni–Holm corrections) and linear multivariable regressions (p < 0.05 considered significant). None of the vision variables were significantly correlated with performance in Para nordic or Para alpine skiing after Bonferroni–Holm corrections were applied. Before applying the corrections, VF extent (ρ = -0.37, p = 0.011), and static VA (ρ = 0.26, p = 0.066) demonstrated the strongest correlations with Para nordic skiing performance; in Para alpine skiing, static VA and CS demonstrated the strongest correlations with downhill (static VA: ρ = 0.54, p = 0.046, CS: ρ = -0.50, p = 0.06), super G (static VA: ρ = 0.50, p = 0.007, CS: ρ = -0.51, p = 0.017), and giant slalom (static VA: ρ = 0.57, p = 0.01, CS: ρ = -0.46, p = 0.017) performance. Dynamic VA and VF were significantly associated with downhill (ρ = 0.593, p = 0.04) and slalom (ρ = -0.49, p = 0.013) performances, respectively. Static VA was a significant predictor of giant slalom [(F(3,11) = 24.71, p < 0.001), and R of 0.87], super G [(F(3,9) = 17.34, p = 0.002), and R of 0.85], and slalom [(F(3,11) = 11.8, p = 0.002), and R of 0.80] performance, but CS and VF were not. Interestingly, static VA and CS were highly correlated in both Para nordic (ρ = -0.60, p < 0.001) and Para alpine (ρ = -0.80, p < 0.001) skiers. Of the vision variables, only static VA and VF were associated with skiing performance and should be included as the in Para nordic and Para alpine classifications. The strong correlations between static VA and CS in these skiers with vision impairment may have masked relationships between CS and skiing performance.

The Relationship Between Visual Function and Performance in Para Swimming

“…At first sight, the difference between these two values may seem substantial. However, in this and other studies, it is rare to find athletes with a binocular VA between 2.6 and 3.5 logMAR (which could be due to the way VA is generally measured [ 10 , 16 , 21 , 23 ]). Indeed, there were no athletes with that level of acuity in our study.…”

“…Caution is warranted though given the low participant numbers within that group (i.e., seven swimmers with light perception and four without) and that the association was only with the mean lateral position in the lane and not with overall race time or any other measures of performance. Moreover, given the relatively low number of athletes with only light perception or no light perception taking part in VI competition [ 10 , 16 , 21 , 23 ], a split within that class would result in two classes with very few athletes and therefore in a relatively low level of competition.…”

“…‘Light perception’ was recorded when the athlete responded correctly 3 out of 4 times. Black/white discrimination was nominally defined as 3.5 logMAR, light perception as 3.7 logMAR, and no light perception as 4.0 logMAR [ 10 , 23 , 36 ]. In alignment with the IPC’s VI classification decision making rules for the single-letter E cards, when multiple cards were used, the card yielding the second-best VA score was taken as the athletes’ true VA (to minimise the chance of erroneous scores with a single better-than-expected result).…”

“…Research in VI rifle shooting demonstrated that only one class was necessary in that sport, because functionally blind athletes could perform just as well as athletes with much less impairment, presumably because in that sport they can effectively rely on the auditory feedback used in the sport to guide the rifle [ 8 – 13 ]. Research has also begun in other VI sports including football [ 14 , 15 ], judo [ 16 – 21 ], skiing [ 22 , 23 ], athletics [ 24 ], goalball [ 25 ], and swimming [ 7 ].…”

Evidence‐based classification in golf for athletes with a vision impairment: A Delphi study

“…To achieve fair inclusion criteria, it is necessary to identify at what level VI starts to affect performance. Such studies have been undertaken for other VI sports such as shooting, Nordic and alpine skiing 7,10,11 . While there has been work that identified 10 D of defocus can impact putting, 29,30 further research is necessary.…”