Cardiopulmonary Physiology and Responses of Ultramarathon Athletes to Prolonged Exercise

Abstract

The purpose of this study was to determine the changes of pulmonary function and autonomic cardiovascular control after an ultramarathon and their relation to performance. Eight entrants to the Canadian National Championship 100-km running race participated in the study. Pulmonary function and 30-s maximum voluntary ventilation (MVV30s) tests were conducted one day before the race and within 5 minutes of race completion. Heart rate and blood pressure data were collected 30 min before and 5 min after the race as well as during a 10-min stand test one day prior to the race. During the race, beat-by-beat R-R interval data were collected over the first and last 20 km. The results showed that MVV30s and MVV30s tidal volumes were reduced postrace (p < 0.001). Prerace supine total harmonic variation (p < 0.01) and prerace MVV values (10 s to 30 s) (p < 0.05) were correlated with race finish time. The changes in pulmonary function and MVV30s values from pre- and postrace were not significantly correlated to race performance. We conclude that maximal sustainable ventilatory power and dynamic autonomic cardiovascular control are important factors in determining overall performance in an ultramarathon.

Lung function and oxygen saturation after participation in Norseman Xtreme Triathlon

“…In line with studies from Hill et al, 3 Blaber et al, 4 and Zarvorsky et al, 24 we found significant reductions in all lung function variables after the race (Table 2). Blaber et al 4 observed that FEV 1 /FVC, MVV 30s , and MVV 30s TV were reduced from baseline to after an ultra‐marathon in eight runners and Hill et al 3 reported declines in FVC (7.1%), FEV 1 (8.4%), and FEF 50 (18.6%), but not in MVV in 12 participants after a long‐distance triathlon.…”

“…The day after the race, 28% still had obstructive features with a reduction in FEV 1 ≥ 10%. This is in line with previous studies in triathletes 3,8,10,16,38 as well as in marathon and ultra‐marathon runners 4,7 . However, the sample size is small in most studies and the included athletes are often at elite level 3‐4,7‐8,10 .…”

“…In addition, the ratio of FEV 1 and forced vital capacity (FVC), FEV 1 /FVC, was reduced after the race. However, only baseline MVV was correlated to race performance and not the changes in MVV from pre‐ to post‐race 4 . Moreover, Hue et al 8 demonstrated that a cycle‐run succession (30 minutes cycling followed by 20 minutes running) induced changes in pulmonary function in 8 national level and 6 elite level triathletes.…”

Heart Rate, Mean Arterial Blood Pressure, and Pulmonary Function Changes Associated With an Ultraendurance Triathlon

“…4,8 Respiratory muscle fatigue could explain the diminished flow rates observed and has been documented after exercise if the intensity level is high or the duration is prolonged to exhaustion. 3,7,8 The further decline of FVC and FEV 1.0 on day 3 could be due to both performing the more cardiorespiratory-demanding 85-km run to near exhaustion on day 3 and the cumulative effects of 3 days of fatiguing competition. Respiratory muscle fatigue induced before high-intensity exercise has been shown to reduce subsequent performance.…”

Maximal and submaximal oxygen uptake efficiency slope: influence of cardiorespiratory variables and maximal dynamic strength

“…Although it has been well accepted that aerobic fitness is highly dependent on cardiorespiratory system [17], several studies have also found a strong association between muscle strength and aerobic fitness [18,19]. Individuals with greater muscle strength could generate lower relative force at the same absolute running intensity.…”