Effects of different types of respiratory muscle training on exercise performance in runners

To compare two different types of respiratory muscle training on exercise performance, a protocol was devised consisting of a combination of a 4-week, 12-session resistive respiratory muscle training (RRMT) followed by a 4-week, 12-session voluntary isocapnic hyperpnea training (VIHT) and conducted in experienced runners (4 men, 4 women). Measurements before and 5 days after training included: pulmonary function (spirometry), maximal inspiratory and expiratory mouth pressures, respiratory endurance time, maximal oxygen uptake (V_O2max), running time to voluntary exhaustion at 80% V_O2max, blood lactate concentration, and minute ventilation. There were no statistically significant differences in pulmonary functions and V_O2max post-RRMT and post-VIHT compared to pre-RMT. Following RRMT the inspiratory muscle strength had improved by 23.8 ± 30% and 18.7 ± 21.4% at rest and immediately after the running test, respectively. RRMT did not increase the time intense voluntary isocapnic ventilation could be maintained during rest while VIHT increased it (237 ± 207.8%). The duration of the endurance run was extended 17.7 ± 6.5% after RRMT and 45.5 ± 14.3% after VIHT.