Increased Susceptibility to Plasma Lipid Peroxidation in Untrained Subjects after an Extreme Mountain Bike Challenge at Moderate Altitude

Abstract

The purpose of this study was to determine whether acute strenuous physical exercise, partially performed under moderate altitude, influences the susceptibility of plasma lipids to peroxidation. Eleven male amateur cyclists took part in a 95-km mountain bike challenge with a cumulative altitude difference of 2340 m. Blood samples were obtained before and immediately after the race in order to determine plasma lipid and lipoprotein concentrations, and to assess the susceptibility of the former to peroxidation. Neither plasma lipid nor lipoprotein levels changed significantly after the race. However, the susceptibility of plasma lipids to peroxidation increased by 71.8 %. We concluded that strenuous physical exercise partially performed under hypoxic conditions increases the susceptibility of plasma lipids to peroxidation in untrained subjects.

Hypoxic training: Clinical benefits on cardiometabolic risk factors

“…Total cholesterol levels reduced from as little as 0.5% to 30% in five out of eight studies [6,10,[26][27][28], although one study [29] reported a significant increase of 4.5 % at 4800m and 4.3% at 3000m.…”

“…While epidemiology studies have reported increased total cholesterol among high altitude dwellers [40], in this review, studies indicated that hypoxic training was able to reduce total cholesterol [6,10,[26][27][28], and this included subjects with obesity and metabolic syndrome. One striking difference between those studies and epidemiology is the inclusion of an exercise regime with concurrent hypoxic training, which would affect findings.…”

Antioxidant defence and inflammatory response in professional road cyclists during a 4-day competition

“…The exercise-induced production of reactive oxygen species is well documented in healthy sedentary (Jammesa, Steinberg, Brégeon, & Delliaux, 2004), trained (Ji, Gomez-Cabrera, & Viñ a, 2006), and non-trained individuals (Ruiz, Ortega, Castillo, Gutierrez, & Agil, 2006). Exercise increases oxygen uptake and almost 2% of the oxygen may be converted to reactive oxygen species.…”

International Journal of Sports Medicine: Progress and Innovation in Cycling Science 2001 - 2007

“…However, Hue et al [9] found that resting thermoregulatory and some haematological variables were unaffected during a 9-day cycling stage race, and Vogt et al [28] found that professional cyclists are not in negative energy balance during intensive pre-season training. In less-trained subjects, Ruiz et al [23] found that a 95-km mountain bike competition held at moderate altitude increased the susceptibility of plasma lipids to peroxidation by about 72%. Such differences between worldclass and recreational cyclists might of course be explained by genetic factors.…”