Sports vision is still a relatively new discipline and its importance in sports performance cannot be overstated because visual information provides approximately 85 to 95% of the sensory information an athlete receives on the playing field.1
In this regard, since maximal exercise is often associated with fatigue and decreases in physical and cognitive performance, it may also be associated with detrimental decreases in visual performance, all of which negatively affects athletic performance and outcomes.
With regards to visual performance, previous literature has demonstrated that prolonged endurance exercise can lead to deterioration in visual skills due to central or brain-based fatigue in the corticospinal motor system.2
Problematically, vision has a multitude of definitions in literature with none being as simple as only seeing3 and in contrast to these findings, other research has demonstrated that strenuous endurance exercise, in the form of cycling and jogging can improve aspects of vision.4
While strenuous prolonged endurance exercise has been reported to affect various aspects of visual performance, it is entirely plausible that just as exercise modality (ie endurance training compared to anaerobic or short-term exercise) has varied effects on physical and cognitive performance, it may also have varied effects on visual performance.
What was the aim of this study?
This study explored how all-out short-term exercise affects visual performance. This information could be used to assist athletes, coaches, conditioning professionals, and vision specialists in the development of strategies to either mitigate or take advantage of all-out exercise to improve visual performance.
Specifically, the study examined if a short-term all-out cycling impacted accommodation facility, saccadic eye movement, speed of recognition, peripheral awareness, hand-eye coordination and visual memory.
What do the results of this study show?
The study showed that a single standardised 30-second all-out cycle session significantly improved accommodation facility, saccadic eye movement, speed of recognition, peripheral awareness and hand-eye coordination, but had no effect on visual memory.
In this regard, it may be that visual memory may be unaffected by exercise because it is supported by an extensive network of brain regions that are responsible for the relationship between perceptual processing and the programming, storage and recall of the resulting neural representations.5
Uniquely, the study showed that some visual tasks, like visual memory, may be more stable, and thus more ‘resistant’ to the effects of exercise. However, further research is needed to confirm these assumptions.
What are the limitations of the work? What further work still needs to be undertaken in this field?
One major constraint of the research was the absence of binocular testing, such as cover tests, phorias or vergences, in the initial optometric assessment before the study. This omission may have resulted in some participants not being screened for conditions like strabismus or amblyopia, which could significantly affect accommodation, saccades, visual-motor integration and visual perceptual skills.
Despite this, the findings of the research have far-reaching implications for athletic performance and concussion management, and further work still needs to be undertaken to determine how long these improvements last following this modality, and indeed other modalities, of exercise.
This is particularly relevant for sports, where even minor enhancements in visual performance during competition can benefit athletes, and where visual task assessments are utilised during sporting events (eg side-line assessments) to evaluate post-injury deficits.
Conclusion
The results of the study suggest that as various physiological systems are influenced differently by the various exercise modalities, so too is it likely that they differentially influence the various aspects of vision.
Therefore, eye care professionals (ECPs) and conditioning professionals should consider all the visual skills or tasks that are required by athletes in their respective sports, and then determine how participation in that sport’s training and competition can influence those visual abilities both in the short and long-term.
Why might this work be important to ECPs?
The findings from this study carry significant implications for various professional fields, including ECPs, conditioning professionals, and healthcare practitioners. These implications extend beyond the immediate scope of this research. The discovery that all-out cycling can enhance multiple facets of visual performance has far-reaching implications.
It suggests that incorporating this type of exercise into baseline and follow-up visual assessments could alter the results, potentially leading to more accurate and comprehensive evaluations. All-out cycling can also be integrated as an integral component of high-intensity anaerobic warm-up routines designed to enhance visual skills, which, in turn, play a crucial role in athletic performance.
Moreover, these findings may have broader applications, especially in scenarios where visual performance assessments are utilised for diagnosing concussions on the side-line during sporting events. The presence of exercise-induced improvements in visual performance may complicate the assessment of potential brain injuries, potentially masking symptoms and making it more challenging to identify concussions accurately and safely determine return to play for athletes.
This highlights the need for a more nuanced approach when employing visual performance assessments in these critical medical contexts.
- Brandon S Shaw, PhD, PhD, is a sport scientist, human movement scientist, and biokineticst, which is an allied healthcare professional specialising in exercise rehabilitation and performance enhancement. In addition to being a researcher at the University of Essex, he is an immediate past board member and audit chairperson of the Medical Research Council (MRC) (SA), and was the vice-dean of Research, Internationalisation and Postgraduate Studies, and professor at the University of Johannesburg. He possesses expertise in the field of sports vision, with a primary emphasis on elucidating the pivotal role of vision in various sports and athletic endeavours. His research delves into the influence of both acute and chronic exercise training on visual performance, elevating the significance of his contributions in this field.
Disclosures
The author(s) declare no potential conflict of interest exists.
Full findings were published in:
Shaw, BS, Breukelman, G, Millard, L, Moran, J, Brown, GA & Shaw, I.(2023). Effects of a maximal cycling all-out anaerobic test on visual performance, Clinical and Experimental Optometry, https://doi.org/10.1080/08164622.2022.2153583.
References
- Nascimento H, Martinez-Perez C, Alvarez-Peregrina C, Sánchez-Tena MÁ. The Role of Social Media in Sports Vision. Int J Environ Res Public Health. 2021; 18(10): 5354. doi:10.3390/ijerph18105354.
- Connell CJW, Thompson B, Turuwhenua J et al. Fatigue-related impairments in oculomotor control are prevented by norepinephrine-dopamine reuptake inhibition. Sci Rep 2017; 7: 42726. doi:10.1038/srep42726.
- Millard, L Shaw, I, Breukelman, GJ, Shaw BS. Visio-spatial skills in athletes: comparison of rugby players and non-athletes. Sport Sci Health. 2021; 17: 137-143. doi:10.1007/s11332-020-00663-1.
- Woods RL, Thomson WD. Effects of exercise on aspects of visual function. Ophthalmic Physiol Opt 1995; 15: 5–12.
- Todd J, Marois R. Capacity limit of visual short term memory in human posterior parietal cortex. Nature. 2004; 428: 751-754. doi:10.1038/nature02466.