The effect of slow-loaded breathing training on the blood pressure response to handgrip exercise in patients with isolated systolic hypertension

Abstract

Isolated systolic hypertension (ISH) is the most common form of hypertension in older people. It is characterized by increased resting systolic blood pressure (sBP) and increased sBP in response to exercise. It has previously been shown that slow breathing training reduces resting sBP, and the objective of the present study was to determine whether it also reduced the blood pressure response to static handgrip exercise. ISH patients aged between 60 and 74 years were randomly divided into a control group (10 subjects, 4 of which were male) that breathed normally and a trained group (10 subjects, 4 of which were male) that trained daily for 8 weeks by slow breathing against an inspiratory resistance of 18 cmHO. Before and immediately after training, subjects underwent a 2-min handgrip test (30% max) followed by 2 min of post-exercise circulatory occlusion (PECO) to assess metaboreflex activity. Training reduced sBP by 10.6 mm Hg (95% confidence interval (CI), -16 to -5 mm Hg, P=0.004), but changes were not observed in the control group. The peak exercise sBP was reduced by 23 mm Hg (95% CI, -16 to -31 mm Hg, P<0.001), while the increase in the sBP above resting was reduced by 12.6 mm Hg (95% CI, -6.9 to -18.2 mm Hg, P=0.002). The sBP during PECO was reduced by 8.9 mm Hg (95% CI, -4 to -14 mm Hg, P=0.008), which is indicative of reduced metaboreflex activity; no such change was observed in the control group. The results demonstrate that conventional treatment of older patients with ISH may be improved in two ways by slow breathing training: resting sBP may be reduced by 10 mm Hg, more than can be achieved by conventional pharmacological therapies, while the response to static exercise may be reduced by approximately twice this value.

Influence of inspiratory threshold load on cardiovascular responses to controlled breathing at 0.1 Hz

“…The low-to-moderate levels of dyspnea reported by our participants with the load of 10 cmH 2 O may be reduced by decreasing the duration of the exercise and by more frequent practice over time. Studies in hypertension patients using long-term practice with loads of 18-20 cmH 2 O have reported good compliance without any specific adverse events (Jones et al, 2010;Sangthong, Ubolsakka-Jones, Pachirat, & Jones, 2016;Ubolsakka-Jones, Sangthong, Khrisanapant, & Jones, 2017).…”

The effects of slow loaded breathing training on exercise blood pressure in isolated systolic hypertension

“…There are also indications that there are changes in the central control of BP in ISH. Older people with ISH also show an exaggerated response to muscle contraction compared with age matched normotensive subjects (Ubolsakka‐Jones et al, ) with evidence of an increased metaboreflex, which is reduced with SLB training (Ubolsakka‐Jones et al, and Figure here), most likely through the same mechanism as with essential hypertension.…”

“…One of the limitations of the handgrip exercise is that BP was registered with an arm cuff rather than using beat‐by‐beat methodology. Although beat‐by‐beat measurements would be desirable, we have argued elsewhere (Ubolsakka‐Jones et al, ; Ubolsakka‐Jones et al, ) that this mainly affects the variance, but not necessarily the mean value of the measurements made at the end of the contraction because it is difficult to be very precise as to when the measurement is taken. The arm cranking exercise presents problems in terms of measuring BP, but without an indwelling arterial line, it is difficult to see how measurements at the ankle could be improved on.…”

“…One of the limitations of the handgrip exercise is that BP was registered with an arm cuff rather than using beat-by-beat methodology. Although beat-by-beat measurements would be desirable, we have argued elsewhere Ubolsakka-Jones et al, 2017) that this mainly affects the variance, but not necessarily the mean value of the measurements made at the end of the contraction because it is difficult to be very precise as to when the measurement is taken.…”

“…Although a rise in BP is a normal and necessary response to exercise, high BP at rest, and abnormally raised pressure during exercise or recovery, are all prognostic for increased risk of stroke (Kurl et al, 2001). Subjects with ISH have exaggerated BP responses to both dynamic and static exercise (Ubolsakka-Jones, Sangthong, Aueyingsak, & Jones, 2016;Ubolsakka-Jones, Sangthong, Khrisanapant, & Jones, 2017) and are thus likely to be in a high-risk category.…”