Abstract
We assessed the mediating role of the breathing pattern adopted during isometric exercise on the intraocular pressure (IOP) response in the back squat and biceps curl exercises. Twenty physically active young adults performed sets of 1-minute isometric effort against a load corresponding to 80% of the maximum load while adopting three different breathing patterns: (i) Constant breathing: 10 cycles consisting of 3 s of inhalation and 3 s of exhalation, (ii) 10-sec Valsalva: 3 cycles consisting of 10 s holding the breath and 10 s of normal breathing, and (iii) 25-sec Valsalva: 2 cycles consisting of 25 s of the Valsalva maneuver and 5 s of normal breathing. A rebound tonometer was used to semi-continuously assesses IOP during the six sets of 1-minute isometric effort (2 exercises × 3 breathing patterns). We found a progressive IOP rise during isometric effort (P < 0.001, = 0.83), with these increases being greater when the breath was held longer (P < 0.001, = 0.58; 25-sec Valsalva > 10-sec Valsalva = constant breathing). There was a trend towards higher IOP values for the back squat in comparison to the biceps curl, although these differences did not reach statistical significance for any breathing pattern (corrected P-value ≥ 0.146, d ≤ 0.69). These findings reveal that glaucoma patients or those at risk should avoid activities in which the breath is held, especially when combined with physical exercise modalities that also promote an increment in IOP values (e.g. isometric contractions).
Acknowledgments
This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. The authors thank all the participants who selflessly collaborated in this research.
Disclosure statement
No potential conflict of interest was reported by the author(s).
ORCID
JESÚS VERA http://orcid.org/0000-0001-8091-2373
ALEJANDRO PEREZ-CASTILLA http://orcid.org/0000-0001-5535-2087
GEORGE-ALEX KOULIERIS http://orcid.org/0000-0003-1610-6240
RAIMUNDO JIMÉNEZ http://orcid.org/0000-0002-8036-2532
AMADOR GARCIA-RAMOS http://orcid.org/0000-0003-0608-8755