The effects of physical activity on intraocular pressure (IOP) and ocular perfusion pressure (OPP) have been documented in several studies.1,2 Findings have shown that isometric training can induce transient IOP elevation and OPP decrease, which are associated with glaucoma development and progression. No study has proven a direct association between isometric training and glaucoma progression, but a number of case reports3-6 have shown worsening of preexisting glaucoma after exercise-related short-term IOP elevation.
Vera et al. describe the short-term effects of bench press to muscular failure against different relative loads (65%, 75%, 85%, and 95% 1RM) on the IOP and OPP of 17 healthy active young men. IOP and blood pressure were measured before and after each set. They found significant IOP increase with the three higher loads, proving a positive association between load and effect. OPP showed a clinically irrelevant reduction independent of the load. Based on this, the authors advise against performing bench press to muscular failure with heavy loads in patients with glaucoma or risk factors.
Advise against performing bench press to muscular failure with heavy loads in patients with glaucoma or risk factors
IOP and OPP are heavily influenced by ocular disease, race, age, sex, exercise type, and position, so resulting effects of this study cannot be extrapolated to other populations or exercises, which is an important limitation pointed out by the authors. Regarding methods, measuring IOP during the exercise would give an additional measurement that could be significant. Also, even though there is no gold-standard for measuring ocular blood flow (OBF), Doppler or optical coherence tomography angiography could provide more detailed and adequate information than OPP in eyes with compromised autoregulation mechanisms. Evaluating the duration of IOP and OPP/OBF changes would also provide valuable information.
Isometric training with heavy loads (triggering Valsalva) is associated with IOP increase
Overall, these findings reinforce evidence that isometric training with heavy loads (triggering Valsalva) is associated with IOP increase. Understanding the possible undesirable effects of exercise is important, however research that can be extrapolated to the population of interest, that can provide more information regarding progression is warranted.