• What is the effect of aerobic exercise intensity on cardiorespiratory fitness in those undergoing cardiac rehabilitation? A systematic review with meta-analysis

      Mitchell, Braden L.; Lock, Merilyn J.; Parfitt, Gaynor; Buckley, John P.; Davison, Kade; Eston, Roger; University of South Australia, University Centre Shrewsbury/University of Chester (BMJ, 2018-08-18)
      18 Objective: Assess the role of exercise intensity on changes in cardiorespiratory fitness (CRF) in 19 patients with cardiac conditions attending exercise-based cardiac rehabilitation. 20 Design: Systematic review with meta-analysis. 21 Data sources: MEDLINE, Embase, CINAHL, SPORTDiscus, PsycINFO and Web of Science. 22 Eligibility criteria for selection: Studies assessing change in CRF (reported as peak oxygen uptake; 23 V̇O2peak) in patients post-myocardial infarction and revascularisation, following exercise-based 24 cardiac rehabilitation. Studies establishing V̇O2peak via symptom-limited exercise test with ventilatory 25 gas analysis and reported intensity of exercise during rehabilitation were included. Studies with 26 mean ejection fraction <40% were excluded. 27 Results: 128 studies including 13,220 patients were included. Interventions were classified as 28 moderate, moderate-to-vigorous or vigorous intensity based on published recommendations. 29 Moderate and moderate-to-vigorous intensity interventions were associated with a moderate 30 increase in relative V̇O2peak (standardised mean difference ± 95% CI = 0.94 ± 0.30 and 0.93 ± 0.17, 31 respectively), and vigorous-intensity exercise with a large increase (1.10 ± 0.25). Moderate and 32 vigorous intensity interventions were associated with moderate improvements in absolute V̇O2peak 33 (0.63 ± 0.34 and 0.93 ± 0.20, respectively), whereas moderate-to-vigorous intensity interventions 34 elicited a large effect (1.27 ± 0.75). Large heterogeneity among studies was observed for all analyses. 35 Subgroup analyses yielded statistically significant, but inconsistent, improvements in CRF. 36 Conclusion: Engagement in exercise-based cardiac rehabilitation was associated with significant 37 improvements in both absolute and relative V̇O2peak. Although exercise of vigorous intensity 38 produced the greatest pooled effect for change in relative V̇O2peak, differences in pooled effects 39 between intensities could not be considered clinically meaningful.
    • Will Plan S put learned societies in jeopardy?

      Purton, Mary; Michelangeli, Francesco; Fésüs, László (Wiley, 2019-02-25)