Influence of body carbohydrate store modification on catecholamine and lactate responses to graded exercise in sedentary and physically active subjects

• Autorzy: Mikulski T. , Ziemba A. , Nazar K.
• Języki publikacji: EN

Abstrakty

EN

Aim of this study was to elucidate the influence of carbohydrate store modification on exercise capacity and catecholamine thresholds. Nine sedentary students and 10 endurance athletes volunteered for the study consisting of four sessions in one-week intervals. During control session (C) subjects performed graded exercise till exhaustion with workload increasing by 50 Watts every 3 min after an overnight fast. Blood lactate and catecholamines were determined at rest, after each workload and at exhaustion. In the evening preceding each of the remaining three sessions subjects performed glycogen reducing exercise lasting 1.5 hrs at 70% HRmax. Till next morning they did not eat any meal but drank water. Two hours before exercise subjects were given either a high-carbohydrate (H-CHO) or a low-carbohydrate (L-CHO) meal of approx. 1000 kcal or remained fasted (F). Depletion of carbohydrate stores enhanced contribution of fat-derived energy substrates at submaximal workloads, but did not influence either maximal oxygen consumption, workload and lactate concentration or lactate threshold. Low carbohydrate availability resulted in elevated concentration of catecholamines only in untrained subjects. Ingestion of a meal either high or low in carbohydrates diminished those changes. Catecholamine thresholds were similar in all sessions and higher in athletes’ group.

Słowa kluczowe

EN

glycogen; human body ability; catecholamine; lactate threshold; carbohydrate; exercise

• Wydawca: -
• Czasopismo: Journal of Physiology and Pharmacology
• Rocznik: 2008
• Tom: 59
• Numer: 3
• Opis fizyczny: p.603-616,fig.,ref.

Twórcy

autor

Mikulski T.

• Polish Academy of Sciences, Pawinskiego 5, 02-106 Warsaw, Poland

autor

Ziemba A.

autor

Nazar K.