Dynamic inspiratory muscle strength and cardiorespiratory fitness based on age and sex

Abstract

Objective: To analyse the relationship between inspiratory muscle strength and cardiorespiratory fitness in healthy trained elderly, according to age and sex.

Method: Descriptive, cross-sectional and prospective study. Of the 153 participants in the EFAM-UV^© multicomponent training program and over 60 years, 87 were assessed for body composition, blood pressure, oxygen saturation, maximum inspiratory pressure and 6-min walking test. As exclusion criteria: smoker, suffering/having suffered respiratory, cardiac, neuromuscular or rib cage disease, suffering/having suffered cognitive deterioration and/or wearing dental prostheses. 67 elderly (73.02 ± 4.54 years) were considered for the final analysis. These measurements were carried out for three non-consecutive days separate by 48 and 72 hours.

Results: Gender differences in maximum inspiratory strength and cardiorespiratory fitness are confirmed. The moderated association between maximum inspiratory strength and cardiorespiratory fitness, assessed by 6-min walking test, (r=0.468; p<0.005) reduces when taking into account the covariates sex (r^s=0.360; p<0.005) and age (r^e=0.397; p<0.005), with lower R² in women (0.113 vs. 0.188).

Conclusion: These results confirm the need of assessing and training the inspiratory muscles in the elderlies, mainly in women, regardless their physical fitness. Future studies should to analyse which factors can influence the association between maximum inspiratory strength and cardiorespiratory fitness (specially, 6-min walking test) beyond age and sex.