Details

Autor(en) / Beteiligte

• Ferreira, Leonardo F.
• Harper, Allison J.
• Townsend, Dana K.
• Lutjemeier, Barbara J.
• Barstow, Thomas J.

Titel

Kinetics of estimated human muscle capillary blood flow during recovery from exercise

Ist Teil von

• Experimental physiology, 2005-09, Vol.90 (5), p.715-726

Ort / Verlag

9600 Garsington Road , Oxford , OX4 2DQ , UK: The Physiological Society

Erscheinungsjahr

2005

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• The kinetic characteristics of muscle capillary blood flow during recovery from exercise are controversial (e.g. one versus two phases). Furthermore, it is not clear how the overall kinetics are temporally associated with muscle oxygen uptake kinetics. To address these issues, we examined the kinetics of estimated from the rearrangement of the Fick equation using the kinetics of pulmonary ( , primary component) and deoxy-haemoglobin concentration ([HHb]) as indices of and C (a − v)O 2 (arterio-venous oxygen difference) kinetics, respectively . (l min −1 ) was measured breath by breath and [HHb] (μm) was measured by near infrared spectroscopy during moderate (M; below lactate threshold, LT) and heavy exercise (H, above LT) in nine subjects. The kinetics of were biphasic, with an initial fast phase (τ I ; M = 9.3 ± 4.9 s and H = 6.0 ± 3.8 s) followed by a slower phase 2 (τ P ; M = 29.9 ± 8.6 s and H = 47.7 ± 26.0 s). For moderate exercise, the overall kinetics of (mean response time [MRT], 36.1 ± 8.6 s) were significantly slower than the kinetics of (τ P ; 27.8 ± 5.3 s) and [HHb] (MRT for [HHb]; 16.2 ± 6.3 s). However, for heavy exercise, there was no significant difference between MRT-[HHb] (34.7 ± 10.4 s) and τ P for (32.3 ± 6.7 s), while MRT for (48.7 ± 21.8 s) was significantly slower than MRT for [HHb] and τ P for . In conclusion, during recovery from exercise the estimated kinetics were biphasic, showing an early rapid decrease in blood flow. In addition, the overall kinetics of were slower than the estimated kinetics.