Effect of a HIIT program performed in different simulated altitude conditions on physiological variables related with strenght and endurance

Abstract

The objective of the study is to investigate the potential impact of cycling High Intensity Interval Training (HIIT) at sea level or simulated altitude has on Aerobic fitness level, blood lactate accumulation and strength, of the lower limbs of untrained individuals to improve performance and develop a method of training. The study was randomly divided into 2 groups (hypoxia/sea level) and for 4 weeks, training was performed twice a week for the duration of the sessions lasted no more than 30 minutes. The training itself consisted of cycling HIIT, working at 85-90% of maximum heart rate during 1-minute sprint intervals, followed by 1- minute rest periods. For the group that exercised at altitude the oxygen saturation was set at approximately 16%. During the first week there were four 1-minute sprints and after each first week the sprints will increase by two repetitions each week. Results show after training program significant increases in maximum oxygen volume (VO2max) (p < 0,001), haemoglobin concentration (p = 0,004), resting heart rate (p < 0,001), lactate threshold in Watt (W) (p < 0,001), Systolic blood pressure (SBP) (p = 0,007), in the moment pre-post in favour post. There were no significant differences between the increases in any of the performance parameters mentioned between groups (p > 0,05). In addition, neither one repetition maximum (1RM) nor diastolic blood pressure (DBP) were significantly changed in the effect moment or group (p>0,05). These data suggest the time expended under normobaric hypoxia conditions is insufficient to improve aerobic and anaerobic capacity at sea level in untrained subjects. Therefore, if there is any advantage in intermittent hypoxia training to improve performance at sea level, it would not appear with a short exposure protocol as in the present study.