Isometric Exercise and Blood Pressure: 12 Weeks of Training and Detraining in the Elderly

Abstract

Background Elderly people are particularly affected by rising systolic blood pressure (SBP). We hypothesized that resting blood pressure (RBP)-reducing isometric exercise training (IET) can be delivered in a group setting with older adults. Methods Participants (63–88 years; N = 19) completed IET at 30% maximum voluntary contraction, 3 days a week for 12 weeks. RBP was measured weekly throughout, plus 6 weeks posttraining. Control participants did not engage in IET (N = 5). Changes in RBP were assessed using a 2-way repeated-measures analysis of variance. Results IET induced significant reductions in SBP (−10.5 mmHg; P < 0.05), but SBP also declined unexpectedly in the control group (−4.5 mmHg; P < 0.05). Diastolic blood pressure declined in the IET group only (−4.7 mmHg; P < 0.05). There were no significant differences between groups for SBP or diastolic blood pressure (P > 0.05). At 6 weeks posttraining, SBP was still 9.4 mmHg below baseline in the IET group only. A unique finding was that the clinically significant RBP reductions persisted for 6 weeks after IET. Conclusions Handgrip IET may be an effective antihypertensive intervention, which persists for several weeks in older adults, even when training ceases.

Isometric Exercise Training and Arterial Hypertension: An Updated Review

“…Early data from Wiley et al [41] also demonstrated that BP reductions returned to baseline values following a 5-week detraining period, while Taylor et al [44] confirmed the suitability of 3 weeks as a 'washout' period to establish baseline BP levels. Conversely, Baross et al [45] found that resting and ambulatory BP reductions seen after an 8-week leg extension intervention remained significantly lower than baseline values following a further 8-week detraining period, which is a finding supported by the recent findings of Gordon et al [70]. Evidently, the exact detraining effects regarding regression toward baseline BP values following IET are not clear and are likely influenced via training parameters such as IET mode, intensity and intervention duration.…”

“…Following this concept, the majority of IET data, including the discussed mechanistic metaanalysis [31], only reflect short-term functional changes with limited information on longitudinally stimulated structural mechanistic adaptations. Baross et al [53] and Gordon et al [70] have both recently evidenced a sustained effect of IET on BP after a detraining period following 8 and 12 weeks of IET, respectively. Given that a rapid detraining effect would be expected if the mechanisms driving such BP reductions were purely functional, this work may therefore imply some degree of sustained structural [70] adaptation.…”

“…Baross et al [53] and Gordon et al [70] have both recently evidenced a sustained effect of IET on BP after a detraining period following 8 and 12 weeks of IET, respectively. Given that a rapid detraining effect would be expected if the mechanisms driving such BP reductions were purely functional, this work may therefore imply some degree of sustained structural [70] adaptation. Furthermore, a recent study [82] documented the longest IET intervention to date of 1 year and reported a significantly reduced TPR as the primary mechanism for the maintained BP reductions.…”