To measure intraocular pressure (IOP) as a function of positional changes of the head during heavy weight lifting.

The subjects of this study were 30 healthy adult males in their twenties to forties. This study investigated their ophthalmic examinations, BMI (body mass index), and 1RM (one repetition maximum) according to the three bench press positions.

The baseline IOP was measured in each position before starting exercise. IOP was measured during pre-exercise and then lift down, lift up when exerting 80% of 1RM in three bench press positions.

Before exercising, the IOP was higher in the lowered head position in the decline bench press (18.20±2.89 mmHg) than in the incline bench press (14.38±2.32 mmHg) ( p <0.001). The IOP increased significantly during the bench press exercise, relative to during the pre-exercise ( p <0.001). Upon lift down, IOP increased by 3.72±1.85 mmHg greater than upon lift up, and mean IOP increased by 2.61±1.63 mmHg ( p <0.001). In our experiments, IOP increased to a maximum of 22.10±2.79 mmHg, measured during lift down in the decline bench press configuration. The BMI and the IOP before exercise showed significant correlation ( p <0.05).

IOP increased more during exercise involving a lower head position. Further study is needed to know the extent to which this result is relevant for glaucoma patients and which activities and head positions during exercise may worsen glaucoma. In the meantime, patients with severe glaucoma may need to avoid lifting heavy objects with a lowered head position.