Effects of Combined Training with Breathing Resistance and Sustained Physical Exertion to Improve Endurance Capacity and Respiratory Muscle Function in Healthy Young Adults

摘要

Peak oxygen uptake (VO2peak) and ventilatory threshold (VT) reflect the capacity for endurance1-3), and improving them is beneficial for health4-6). To date, many different methods of training have been recommended for effectively improving endurance capacity, and the effectiveness of these methods has been examined. Rhythmic physical exercise such as running or cycling leads to improved VO, t and VT3) Endurance capacity depends on respiratory function in addition to circulatory and muscular function, and for this reason, there has recently been considerable interest in the relationship between respiratory muscle training, which aims to improve respiratory muscle function, and cardio-respiratory endurance. Some studies have reported that in-spiratory muscle training during rest improves the cardiore-spiratory endurance of patients with weakened respiratory muscles and that of healthy adults7 n whereas other studies have reported no effect12-15). Thus, there is no consensus of opinion. In addition, with inspiratory muscle training during rest, it is difficult to combine an increased ventilation requirement brought about by an increase in required oxygen intake with respiratory load. Therefore it is difficult to continually carry out inspiratory muscle training during rest by applying resistance to deep breathing. Physical exercise under hypoxic conditions has been shown to be very effective at increasing endurance capacity16), but it is not possible to apply resistance to the respiratory muscles during this type of training. The subject needs to go to a location at a high altitude or use an apparatus to control the partial pressure of oxygen; thus, the training is difficult from the point of view of time and the financial costs involved.