Short-term overtraining: effects on performance, circulatory responses, and heart rate variability

Purpose and Methods: Nine elite canoeists were investigated concerning changes in performance, heart rate variability (HRV), and blood-chemical parameters over a 6-d training camp. The training regimen consisted of cross-country skiing and strength training, in total 13.0 ± 1.6 h, corresponding to a 50% increase in training load. Results: Time to exhaustion (RunT) decreased from 19.1 ± 1.0 to 18.0 ± 1.2 min (P < 0.05). V[dot]O2max and max lactate (Lamax) both decreased significantly (P < 0.05) over the training period (4.99 ± 0.97 to 4.74 ± 0.98 L·min-1 and from 10.08 ± 1.25 to 8.98 ± 1.03 mmol·L-1 respectively). Heart rates (HR) decreased significantly at all workloads. Plasma volume increased by 7 ± 7% (P < 0.05). Resting cortisol, decreased from 677 ± 244 to 492 ± 222 nmol·L-1 (P < 0.05), whereas resting levels of adrenaline and noradrenaline remained unchanged. The change between tests in RunT correlated significantly with the change in HRmax (r = 0.79; P = 0.01). There were no group changes in high or low frequency HRV, neither at rest nor following a tilt. Conclusions: The reduced maximal performance indicates a state of fatigue/overreaching and peripheral factors are suggested to limit performance even though HRmax and Lamax both were reduced. The reduced submaximal heart rates are probably a result of increased plasma volume. HRV in this group didn't seem to be affected by short-term overtraining.
© Copyright 2000 Medicine & Science in Sports & Exercise. Lippincott Williams & Wilkins. Kaikki oikeudet pidätetään.

Aiheet: risti melonta kierto ylikunto syke suorituskyky
Aihealueet: kestävyys urheilu biologiset ja lääketieteelliset tieteet
Julkaisussa: Medicine & Science in Sports & Exercise
Julkaistu: 2000
Vuosikerta: 32
Numero: 8
Sivuja: 1480-1484
Julkaisutyypit: artikkeli
Kieli: englanti (kieli)
Taso: kehittynyt