Young men with poor cardiorespiratory fitness combined with lower testosterone have high levels of oxidized LDL lipids--being fit alters this relationship.

PURPOSE: We hypothesized that lower androgen status together with poor physical fitness associates with atherogenic lipid profile and oxidative stress.

METHODS: Volunteered young men (N = 846, mean age 25.1 ± 4.6 years) were categorized into unfit, average fit, and fit groups according to tertiles of maximal oxygen uptake, series of muscle endurance tests, and maximal upper and lower body strength. Furthermore, concentrations of serum testosterone (TT) and free testosterone (FT) were determined to divide participants into lower and higher testosterone (loTT, hiTT) and free testosterone (loFT, hiFT) subgroups, using medians as cut-off points. The participants were divided into subgroups according to Fitness × Testosterone (Unfit/Average Fit/ Fit × Low/High TT/FT), and the concentrations of serum lipids and ox-LDL were measured.

RESULTS: The loTT/unfit cardiorespiratory subgroup had 29% higher concentration of ox-LDL compared with the loTT/fit cardiorespiratory subgroup (p = .044). The loTT / unfit cardiorespiratory subgroup had a significantly higher ratio of ox-LDL/HDL-cholesterol compared with the other five TT subgroups (p < .05, in all). While ox-LDL showed a gradual form of decrease from unfit to fit in loTT cardiorespiratory subgroups, no differences were seen in muscular fitness or maximal strength (upper and lower body) subgroups.

CONCLUSIONS: Young men with poor cardiorespiratory fitness together with lower levels of TT have higher concentrations of ox-LDL. Good cardiorespiratory fitness combined with lower androgen levels is not related to atherogenic lipid profile. The combination of poor muscular fitness, or maximal muscle strength, and lower TT levels does not cause atherogenic lipid profile.