Vision Corrections for Presbyopic Orienteers Executive Summary

Purpose: The study by Keziah Latham, Louis P. H. Abbott, and Matthew A. Timmis evaluates visual challenges and refractive correction solutions for presbyopic orienteers (aged $40$ years and older).
Participants: $469$ respondents ( $195$ women, $274$ men) with a median age category of $55$ to $59$ years.
Methods: An online questionnaire via Qualtrics collected data on demographics, participation, and visual corrections used in everyday life vs. orienteering.
Significance: Orienteering requires high visual clarity for near-distance map reading and far-distance terrain navigation while physically active.

No Distance Correction Group ( $n = 187$ ):
- "Off the shelf" reading spectacles: $n = 95$ .
- Compass magnifier: $n = 24$ .
- No adaptations: $n = 23$ .
Distance Refractive Correction Group ( $n = 277$ ):
- Progressive addition spectacles (varifocals): $n = 96$ .
- Monovision contact lenses: $n = 63$ .
- Multifocal contact lenses: $n = 31$ .
- Single vision contact lenses: $n = 27$ .
Adaptations: $57.4\%$ of participants specifically purchased vision correction for the sport. Key changes for sport include using higher reading additions and opting for contact lenses to avoid frame obstruction.

Map Detail ( $29.9\%$ ): Difficulty reading fine contour lines, fence gaps, and small passages, especially on $1:10K$ maps.
Lens Obstruction ( $24.3\%$ ): Fogging from perspiration and rain droplets on spectacles or magnifiers.
Low Lighting ( $21.1\%$ ): Navigating dense woodland or technical terrain during the daytime with insufficient light.
Terrain Navigation: Challenges in switching focus between the map and the ground at the athlete's feet, particularly with the inferior field blur caused by reading additions.

Varifocal Spectacles:
- Advantages: Clarity for both map and terrain ( $68.7\%$ ).
- Disadvantages: Significant issues with lens obstruction ( $39.6\%$ ).
Monovision Contact Lenses:
- Advantages: Prevents fogging/rain obstruction ( $34.8\%$ ) and aids map detail ( $29.2\%$ ).
- Disadvantages: Issues with switching between map and terrain clarity ( $34.4\%$ ) and loss of binocularity ( $10.9\%$ ).
Compass Magnifiers: Provide excellent map detail but suffer from a small field of view ( $37.5\%$ ).
Reading Spectacles: "Off the shelf" options like Vapro SRG-13 or Frenson fog-free lenses are common for those requiring only near correction.

Engagement: $46.0\%$ of participants asked an eye care professional (optometrist or dispensing optician) for advice.
Satisfaction: Advice received was $60.0\%$ negative and $40.0\%$ positive, indicating a need for better clinical understanding of the sport's specific demands.
Recommendations for Practitioners:
- Perform task-specific analysis using actual orienteering maps during eye examinations.
- Balance the need for higher reading additions for fine detail against the risk of blurring the ground at the athlete's feet.
- Discuss contact lenses to mitigate weather-related lens obstruction.

Optimal correction is highly individual and often requires a compromise between different viewing distances.
Practitioners should consider higher-than-normal reading additions and moisture-resistant solutions (contact lenses) for active presbyopes.
Personalized care and trialing different options (e.g., in low-stakes local events) are essential to finding the best fit for an orienteer's specific refractive error and terrain needs.