Can exercise lower intraocular pressure (IOP)?

The Effect of Exercise on Intraocular Pressure

Regular moderate-intensity aerobic exercise can significantly reduce intraocular pressure (IOP) and may be beneficial as an adjunctive measure for IOP management in glaucoma patients. 1

Types of Exercise and Their Effects on IOP

Beneficial Exercise Types

• Moderate-intensity aerobic exercise:

  • Produces transient reductions in IOP 2
  • In a recent study, 30 minutes of moderate aerobic exercise on a treadmill significantly decreased IOP in both healthy and primary open-angle glaucoma (POAG) eyes 1
  • POAG eyes showed a greater degree of IOP reduction compared to healthy eyes 1

• Regular exercise program:

  • A 6-week supervised exercise program focusing on aerobic exercise and strength training resulted in a statistically significant reduction of -2.18 ± 2.25 mmHg in IOP among healthy individuals 3

Exercise Types to Avoid

• High-intensity resistance exercise and weight-lifting:
  • Lead to transient elevations in IOP 2
  • Isometric resistance exercises of the lower limbs can increase IOP 4
  • People with glaucoma or at high risk should perform isometric exercise with caution 4

Mechanisms of IOP Reduction

Exercise appears to affect IOP through multiple mechanisms:

• Expansion of Schlemm's canal: Aerobic exercise significantly increases the average cross-sectional area and diameter of Schlemm's canal in both healthy and POAG eyes 1
• Hypocapnia: Isometric exercise results in an acute decrease in IOP, which correlates with hypocapnia 5
• Physical fitness: Associated with lower baseline IOP but diminished acute IOP-lowering response to exercise 5

Clinical Implications

• Greater benefit in glaucoma patients: IOP-lowering effects of exercise are greater in glaucoma patients than in healthy subjects 5
• Short-term effects: Upon cessation of regular exercise, IOP values return to pre-trained levels within 1 month 5
• Ocular blood flow: In healthy subjects, ocular blood flow remains unchanged during exercise due to vascular autoregulation, which fails at ocular perfusion pressures greater than 70% above baseline 5

Recommendations for Clinical Practice

While the American Academy of Ophthalmology guidelines primarily focus on medical, laser, and surgical treatments for glaucoma management 6, the evidence suggests that exercise can be a valuable adjunctive approach:

1. Consider recommending moderate-intensity aerobic exercise (such as brisk walking, jogging, or cycling) for patients with elevated IOP or glaucoma
2. Advise against high-intensity resistance training for patients with advanced glaucoma or poorly controlled IOP
3. Suggest a regular exercise program of at least 30 minutes, 3 times per week for optimal IOP-lowering effects 3
4. Monitor IOP response to exercise in patients with glaucoma to assess individual benefits

Limitations and Future Directions

• Long-term effects of exercise on glaucoma prevention and progression remain unknown 5
• Further longitudinal studies are needed to validate exercise as a beneficial lifestyle modification in glaucoma management 2
• The role of exercise in glaucoma management deserves further investigation 5

While medical therapy remains the primary approach for IOP control in glaucoma management 6, incorporating regular moderate-intensity aerobic exercise appears to provide additional benefits for IOP reduction and may positively affect the dimensions of Schlemm's canal, potentially improving aqueous outflow.