Influence of age and gender on cardiovascular response to isometric exercise in apparently healthy individuals

Abstract

Objective Static exercises are an integral aspect of patient rehabilitation and are employed in advanced strength and endurance training programmes. Exercise is a form of self-induced stress leading to circulatory and respiratory changes, therefore, this study sought to determine the influence of age and gender on the cardiovascular responses of apparently healthy individuals to isometric/static exercises. Methodology Sixty apparently healthy individuals (30 males and 30 females) participated in this study. Their ages ranged between 21–50 years and were grouped into 21–30 years, 31–40 years and 41–50 years. Each participant carried out and maintained 30% of maximal isometric voluntary contraction (MIVC) using hand grip for 1, 2 and 3 minutes respectively, with 30-minutes rest period. Systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured and recorded, at rest, and during each of the sustained contractions. Results There was a statistically significant increase (p <0.05) in the mean SBP, DBP and HR at rest and with every increase in duration (that is, from 1 minute to 3 minutes) of static handgrip contraction, maintained at 30% MIVC in the 3 groups; except for HR for group one (that is, 21–30 years). There was no gender difference (p >0.05) in SBP and DBP of the participants within the 3 groups, although male participants, particularly in group 2 had higher SBP. There was also a statistically significant increase in the HR of female participants compared to the males in group 2. Isometric contraction for 3 minutes produced the greatest change (increase) in cardiovascular parameter across all the groups but more marked among participants in group 2 (that is, 31–40 years). Conclusion The study concluded that submaximal (30% MIVC) isometric upper limb exercise increase blood pressure and heart rate in both sexes, with greatest values when the exercise was sustained for 3 minutes. Hence, efforts should be made to monitor cardiovascular parameters prior to prescribing safe level of isometric exercise. Also, 3 minutes of static/isometric exercises may be avoided, particularly during the rehabilitation of patient with cardiovascular disease.