Abstract
Background: Respiratory muscle endurance (RME) has been evaluated in a wide range of populations. However, a variety of tests have been used to evaluate RME and the results of some studies have been conflicting.
Aim: to evaluate the effects of respiratory muscle training (RMT) on RME and to determine which RME test that can show consistent changes after RMT.
Methods: Electronic searches were conducted in EMBASE, MEDLINE, COCHRANE CENTRAL, CINHAL and SPORTDiscus. PEDro scale was used for quality assessment and meta-analysis was performed to compare effect sizes of different RME tests.
Results: Twenty studies met inclusion criteria, mean PEDro score was 6 for athletes and 5.6 non-athletes. Isocapnic hyperpnea training was performed in 40% of the studies. Meta-analysis showed that RMT improves RME in athletes (P=0.0007) and non-athletes (P=0.002). Subgroup analysis showed differences among RME tests; maximal sustainable ventilatory capacity (MSVC) and maximal sustainable threshold loading (MSTL) tests demonstrated significant changes after RMT (P=0.007; P=0.003 respectively) compared to maximal voluntary ventilation (MVV) (P=0.11) test in athletes. The effect size reflected by the MSVC was greater compared to the MVV in the studies that performed both MSVC and MVV tests.
Conclusion: Results provide evidence that RMT improves RME in athletes and non-athletes and the longer endurance tests to measure RME such as the MSVC, MSTL and maximal incremental threshold loading MITL tests are a more sensitive measure to show changes after RMT than the shorter MVV. MVV showed a limited response to RMT and this test can fail to show actual improvements in RME.
- Copyright ©ERS 2015