Physiological Response Differences between Run and Cycle High Intensity Interval Training Program in Recreational Middle Age Female Runners

Abstract

The aim of this investigation was to compare the changes in endurance running performance and physiological variables after a four-week period of high intensity interval training (HIIT) in either running or cycling in female athletes. Fourteen recreational female runners (age = 42 10 yr, height = 1.67 0.06 m, body mass = 61.6 10.4 kg, body mass index (BMI) = 22.2 3.4 kg.m^-2) were randomly allocated to one of two HIIT training groups: running (HIIT_run) or cycling (HIIT_bike). Each group performed two HIIT sessions per week for 4 weeks, which consisted of 6 x 2 min at 95% of maximal heart rate (HR_max) and 4 x 1 min all out efforts. Maximal oxygen consumption (VO_2max) in treadmill running increased significantly after the HIIT_run (p < 0.01, ES = 0.6) but remained unchanged in HIIT_bike. However, HIIT_bike improved average velocity in a 10 km running time trial (TT_run) (p < 0.05, ES = -0.4), whereas, no changes were found for the HIIT_run group. Analysing the first and last HIIT sessions, for HIIT_run only the average rate of perceived exertion (RPE_av) increased significantly, whereas, performance variables such as average heart rate (HR_av) and average pace (pace_av) remained unchanged. HIIT_bike enhanced significantly the average speed of HIIT sets (speed_av) and the peak power output (PPO) of the session, as well as, the RPE_av and delayed onset muscle soreness immediately after HIIT session (DOMS_post) were increased significantly. A regime of HIIT in cycling may evoke increases in female recreational runners' power, which may be related with improvements in a 10 km TT_run independent of changes in aerobic capacity. This may be advantageous in order to avoid overuse running related injuries.

Keywords: aerobic capacity; endurance; gender; intermittent training; muscle damage.

Figure 1.

Comparison between A) HIIT_run and B) HIIT_bike for CK pre, immediately post and 24-hour after HIIT session. Variables: Creatine Kinase values pre session (pre); Creatine Kinase values immediately post session (post); CK values 24 hour after the session (24 after); First HIIT session of the program (1st HIIT); last session of the program (8th HIIT).