Dynamic plantar flexion exercise increased peritendinous blood flow 7-fold and decreased O2 saturation from 58% to 52% (P<0.05), indicating coupling of blood flow to oxidative metabolism.
Observational (n=7)
Does dynamic exercise affect blood flow and oxygenation in peritendinous tissue and calf muscle in humans?
Blood flow is coupled to oxidative metabolism in both calf muscle and peritendinous regions during dynamic exercise, though peak peritendinous flow reaches only approximately 20% of its maximal capacity.
p-value: p=<0.05
Circulation around tendons may act as a shunt for muscle during exercise. The perfusion and oxygenation of Achilles' peritendinous tissue was measured in parallel with that of calf muscle during exercise to determine (1) whether blood flow is restricted in peritendinous tissue during exercise, and (2) whether blood flow is coupled to oxidative metabolism. 2. Seven individuals performed dynamic plantar flexion from 1 to 9 W. Radial artery and popliteal venous blood were sampled for O2, peritendinous blood flow was determined by 133Xe-washout, calf blood flow by plethysmography, cardiac output by dye dilution, arterial pressure by an arterial catheter-transducer, and muscle and peritendinous O2 saturation by spatially resolved spectroscopy (SRS). 3. Calf blood flow rose 20-fold with exercise, reaching 44 +/- 7 ml (100 g)-1 min-1 (mean +/- s.e.m. ) at 9 W, while Achilles' peritendinous flow increased (7-fold) to 14 +/- 4 ml (100 g)-1 min-1, which was 18 % of the maximal flow established during reactive hyperaemia. SRS-O2 saturation fell both in muscle (from 66 +/- 2 % at rest to 57 +/- 3 %, P < 0.05) and in peritendinous regions (58 +/- 4 to 52 +/- 4 %, P < 0.05) during exercise along with a rise in leg vascular conductance and microvascular haemoglobin volume, despite elevated systemic vascular resistance. 4. The parallel rise in calf muscle and peritendinous blood flow and fall in O2 saturation during exercise indicate that blood flow is coupled to oxidative metabolism in both tissue regions. Increased leg vascular conductance accompanied by elevated microvascular haemoglobin volume reflect vasodilatation in both muscle and peritendinous regions. However, peak exercise peritendinous blood flow reaches only approximately 20 % of its maximal blood flow capacity.
Boushel et al. (Sat,) reported a observational. Dynamic plantar flexion exercise vs. Rest was evaluated on Perfusion and oxygenation of Achilles' peritendinous tissue and calf muscle (p=<0.05). Dynamic plantar flexion exercise increased peritendinous blood flow 7-fold and decreased O2 saturation from 58% to 52% (P<0.05), indicating coupling of blood flow to oxidative metabolism.