Growth hormone responses to treadmill sprinting in sprint- and endurance-trained athletes

Abstract

The purpose of the present study was to examine the growth hormone (GH) response to treadmill sprinting in male (M) and female (F) sprint- and endurance-trained athletes. A group of 11 sprint-trained (ST; 6M, 5F) and 12 endurance-trained (ET; 6M, 6F) athletes performed a maximal 30-s sprint on a nonmotorized treadmill. Peak power and mean power expressed in watts or in watts per kilogram body mass were higher in ST than in ET (P < 0.01) and in the men compared to the women (P < 0.01). Serum GH was greater in ST than in ET athletes, but was not statistically significantly different between the men and the women [mean peak GH: ST 72.4 (SEM 12.5) compared to ET 26.3 (SEM 4.9) mU.1(-1), P < 0.01; men 59.8 (SEM 13.3) compared to the women 35.8 (SEM 7.4) mU.1(-1), n.s.]. Plasma ammonia and blood lactate concentrations were higher and blood pH lower during 1 h of recovery after the sprint in ST compared to ET (all P < 0.01). Multiple log linear regression showed that 82% of the variation in the serum peak GH response was explained by the peak power output and peak blood lactate response to the sprint. As serum GH was still approximately ten times the basal value in ST athletes after 1 h of recovery, it is suggested that the exercise-induced increase in GH could have important physiological effects in this group of athletes, including increased protein synthesis and sparing of protein degradation leading to maintained or increased muscle mass.

The effect of increased lipid intake on hormonal responses during aerobic exercise in endurance-trained men

“…Importantly, carbohydrate and protein intake was identical in both diets. Endurance-trained male athletes were chosen in order to investigate a homogeneous study population without possible gender-specific (28) or training-related confounding factors of hormonal response (29).…”

Analýza efektu vysoce intenzivního intervalového tréninku (HIIT)

“…Proto se EPOC jeví jako jeden z klíčových mechanismů pro redukci tuků při HIIT (respektive jejich lepší oxidaci). Také vyšší úroveň HGH zaznamenaná po HIIT se může podílet na nárůstu energetického výdeje, a tím i oxidaci tuků (Nevill et al, 1996).…”

Biological Responses to Four Events of the Modern Pentathlon in Male and Female Athletes

“…sta tus tre nin go wy i ro dzaj wy sił ku. Po krót kich, ana ero bo wych wy sił kach (Win ga te), re ak cje GH u sprin te rów by ły sil niej sze niż u bie ga czy tre nu ją cych wy trzy ma łość [23]. Ob ni że nie od po wie dzi GH na trening opo ro wy od no to wa no po se rii sprin tów [24] lub gdy 60 mi nut wcze śniej wy ko na no wy si łek o cha rak terze wy trzy ma ło ścio wym [25].…”