Premium
Kinetics of estimated human muscle capillary blood flow during recovery from exercise
Author(s) -
Ferreira Leonardo F.,
Harper Allison J.,
Townsend Dana K.,
Lutjemeier Barbara J.,
Barstow Thomas J.
Publication year - 2005
Publication title -
experimental physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.925
H-Index - 101
eISSN - 1469-445X
pISSN - 0958-0670
DOI - 10.1113/expphysiol.2005.030189
Subject(s) - blood flow , kinetics , human muscle , capillary action , cardiology , medicine , chemistry , skeletal muscle , thermodynamics , physics , quantum mechanics
The kinetic characteristics of muscle capillary blood flowduring recovery from exercise are controversial (e.g. one versus two phases). Furthermore, it is not clear how the overallkinetics are temporally associated with muscle oxygen uptakekinetics. To address these issues, we examined the kinetics ofestimated from the rearrangement of the Fick equationusing 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.