Application of FT-IR spectrometry to determine the global metabolic adaptations to physical conditioning in sportsmen

Global metabolic adaptations to physical conditioning were described in 15 subjects by FT-IR spectrometry as the method allowed determination of glucose (Glc), lactate (La), glycerol, triglycerides (TG), fatty acyl moieties (FAM), and total amino acids plasma concentrations. Subtraction of plasma FT-IR spectra obtained at resting state from the exercise spectra also allowed determination of the biomolecular response to exercise. On week 1, exercise induced a transient hypoglycemia, a lactatemia increase of 153 %, a FAM depletion of 27 %, and a TG concentration decrease of 28 %. Protein contents increased by 2 %, but these were partly catabolized for amino acid supply (+27 %), suggesting an important metabolic stress during exercise. On week 3, exercise hypoglycemia had disappeared, lactate increase was diminished by 91 %, TG contents were decreased by 14 %, and proteins and amino acids exhibited higher absorption increases. On week 5, TG and FAM concentrations were markedly increased during exercise, protein absorption was still increased (+9 %), but amino acid blood release was diminished by 81 %. These results described positive adaptations to training. Furthermore, FAM concentration could be determined from plasma FT-IR spectra by using the 2996-2819 cm(-1) spectral area [v(as)(CH3), v(as)(CH2), v(s)(CH3), and v(s)(CH2) absorbance; 0.82 mMol(.)L(-1), a.u. cm(-1)], as well as for amino acid concentration by using the v(COO-) spectral area (1430-1360 cm(-1); 0.062 g(.)L(-1), a.u. x cm(-1)). FT-IR spectrometry was useful to determine simultaneously various plasma concentrations and most of the biomolecular changes through successive samples.