| Popis: |
Several recent studies have shown that consuming amino acid-rich compounds improves tendon collagen content and biomechanical properties. Yet, it is not clear if the consumption of amino acids alters local (peritendinous) amino acid concentrations. If aging or exercise influence local amino acid concentrations in conjunction with an amino acid bolus is also not known. We conducted two studies. In Study 1, young women (n=7, 25+/-2 yrs.) completed two identical resistance training sessions with either essential amino acid (EAA) or placebo consumption. In Study 2, an EAA bolus identical to Study 1 was given to younger (n=7; 27+/-1 yr.) and older adults (n=6; 68+/-2 yrs.). Microdialysis was used to determine Achilles peritendinous amino acid and pro-collagen I⍺1 (a marker of collagen synthesis) concentrations. In Study 1, amino acid consumption increased peritendinous concentrations of all EAA except histidine (p0.05) increased with time (p0.05) was unaffected by exercise, EAA, or aging (p>0.05). Our findings demonstrate that: 1) when not combined with exercise, an oral EAA bolus leads to only modest increases in Achilles peritendinous amino acid concentrations, 2) when combined with resistance exercise, EAA consumption resulted in greater peritendinous amino acid concentrations compared to no exercise, 3) the basal concentrations of most amino acids were greater in older adults, and 4) neither the EAA bolus nor exercise altered peritendinous pro-collagen concentrations. |
