LAUSR

Objective: Isometric exercise training (IHT) may be a practical, inexpensive and time efficient modality to reduce blood pressure (BP). We report preliminary exercise adherence data from HoldAge (NCT04275037) among older adults with high-normal BP to stage I hypertension. Design and method: Participants performed a total of 24 sessions of IHT or aerobic exercise training (AET), 3 times/week, for 8 wks. IHT was 4x45 min contractions, alternatively with both hands, at an intensity of 50% of the maximum voluntary contraction, with 1 min rest between sets. AET was walking 20–30 min at an intensity of 50–70% of the estimated peak maximal oxygen consumption (VO2peak) assessed with a submaximal step test. The attention control (AC) group received standardized optimal medical care including lifestyle advice. The adherence to IHT was a mean quality score recorded in the digital dynamometer, representing the % time participants performed the exercise sessions at the prescribed intensity. The adherence to AET was the time spent exercising at the prescribed intensity, recorded with a heart rate monitor. Results: 95 eligible people were contacted to participate and 72 agreed to participate (76%). Of these, 49 participants have finished the study (IHT:19; AET:18; AC:12) with 4 dropouts (AET:1; AC:3). Three participants changed their antihypertensive medication and were excluded (AET:1; AC:2). IHT had a self-reported exercise adherence of 96.7 ± 9.3%, while data downloaded from the exercise devices showed an adherence of 88.6 ± 13.9% of the sessions, with 2.3 ± 3.3% incomplete sessions. IHT registered a mean quality score of 91.8 ± 11.2% for the right hand (mean strength: 22.6 ± 7.7 kg), 91.7 ± 13.5% for the left-hand (mean strength: 20.9 ± 8.6 kg), and 91.6 ± 12.2% for both hands. AET had a self-reported exercise adherence of 83.8 ± 33.6%, consistent with the data downloaded from the heart rate monitors. AET participants spent a total of 578.1 ± 263.6 min exercising, of which 153.3 ± 152.4 min (22.6 ± 23.2%) was spent walking at the prescribed intensity, 286.3 ± 210.5 min (45.4 ± 35.2%) was below and 137.8 ± 154.7 minutes (19.4 ± 21.7%) was above. Conclusions: Exercise adherence in HoldAge is high in both IHT and AET, but the time spent at the prescribed intensity appears to be higher in IHT than AET.