Paul Delia rarely says anything best -- instead, he writes columns (without references and with numerous things indicating he is ignorant of, or holding back purposefully, large amounts of data from the literature), which attack the "science" of products that AST has incentive to remove market share from.
Here are some studies on increased blood flow during exercise:
J Appl Physiol. 2003 Jan;94(1):6-10. Epub 2002 Aug 16. Related Articles, Links
Comment in:
J Appl Physiol. 2003 Jan;94(1):3-5.
Muscle pump does not enhance blood flow in exercising skeletal muscle.
Hamann JJ, Valic Z, Buckwalter JB, Clifford PS.
Medical College of Wisconsin and Veterans Affairs Medical Center, Milwaukee 53295, USA.
The muscle pump theory holds that contraction aids muscle perfusion by emptying the venous circulation, which lowers venous pressure during relaxation and increases the pressure gradient across the muscle. We reasoned that the influence of a reduction in venous pressure could be determined after maximal pharmacological vasodilation, in which the changes in vascular tone would be minimized. Mongrel dogs (n = 7), instrumented for measurement of hindlimb blood flow, ran on a treadmill during continuous intra-arterial infusion of saline or adenosine (15-35 mg/min). Adenosine infusion was initiated at rest to achieve the highest blood flow possible. Peak hindlimb blood flow during exercise increased from baseline by 438 +/- 34 ml/min under saline conditions but decreased by 27 +/- 18 ml/min during adenosine infusion. The absence of an increase in blood flow in the vasodilated limb indicates that any change in venous pressure elicited by the muscle pump was not adequate to elevate hindlimb blood flow. The implication of this finding is that the hyperemic response to exercise is primarily attributable to vasodilation in the skeletal muscle vasculature.
PMID: 12391132 [PubMed - indexed for MEDLINE]
J Appl Physiol. 1998 Nov;85(5):1649-54. Related Articles, Links
Skeletal muscle vasodilation at the onset of exercise.
Buckwalter JB, Ruble SB, Mueller PJ, Clifford PS.
Departments of Anesthesiology and Physiology, Medical College of Wisconsin and Veterans Affairs Medical Center, Milwaukee, Wisconsin 53295, USA.
The purpose of this study was to determine whether beta-adrenergic or muscarinic receptors are involved in skeletal muscle vasodilation at the onset of exercise. Mongrel dogs (n = 7) were instrumented with flow probes on both external iliac arteries and a catheter in one femoral artery. Propranolol (1 mg), atropine (500 microgram), both drugs, or saline was infused intra-arterially immediately before treadmill exercise at 3 miles/h, 0% grade. Immediate and rapid increases in iliac blood flow occurred with initiation of exercise under all conditions. Peak blood flows were not significantly different among conditions (682 +/- 35, 646 +/- 49, 637 +/- 68, and 705 +/- 50 ml/min, respectively). Although the doses of antagonists employed had no effect on heart rate or systemic blood pressure, they were adequate to abolish agonist-induced increases in iliac blood flow. Because neither propranolol nor atropine affected iliac blood flow, we conclude that activation of beta-adrenergic and muscarinic receptors is not essential for the rapid vasodilation in active skeletal muscle at the onset of exercise in dogs.
PMID: 9804565 [PubMed - indexed for MEDLINE]
J Appl Physiol. 1997 Dec;83(6):2037-42. Related Articles, Links
Autonomic control of skeletal muscle vasodilation during exercise.
Buckwalter JB, Mueller PJ, Clifford PS.
Department of Anesthesiology, Veterans Affairs Medical Center and Medical College of Wisconsin, Milwaukee, Wisconsin 53295, USA.
Despite extensive investigation, the control of blood flow during dynamic exercise is not fully understood. The purpose of this study was to determine whether beta-adrenergic or muscarinic receptors are involved in the vasodilation in exercising skeletal muscle. Six mongrel dogs were instrumented with ultrasonic flow probes on both external iliac arteries and with a catheter in a branch of one femoral artery. The dogs exercised on a treadmill at 6 miles/h while drugs were injected intra-arterially into one hindlimb. Isoproterenol (0.2 microg) or acetylcholine (1 microg) elicited increases in iliac blood flow of 89.8 +/- 14.4 and 95.6 +/- 17.4%, respectively, without affecting systemic blood pressure or blood flow in the contralateral iliac artery. Intra-arterial propranolol (1 mg) or atropine (500 microg) had no effect on iliac blood flow, although they abolished the isoproterenol and acetylcholine-induced increases in iliac blood flow. These data indicate that exogenous activation of beta-adrenergic or muscarinic receptors in the hindlimb vasculature increases blood flow to dynamically exercising muscle. More importantly, because neither propranolol nor atropine affected iliac blood flow, we conclude that beta-adrenergic and muscarinic receptors are not involved in the control of blood flow to skeletal muscle during moderate steady-state dynamic exercise in dogs.
PMID: 9390978 [PubMed - indexed for MEDLINE]
I could supply 100 more.
Why do you suppose the body increases blood flow to the muscle during exercise, if not to transport more nutrients to the cell.
It does not make a great deal of evolutionary sense (or common sense), to have a system which drastically increases blood flow (and, blood carries nutrients to cells) to the tissue with a higher demand for said nutrients, "coincidentally" right when that increased demand occurs, only to have it completely go to waste -- because, according to Delia, the one and only thing that increases the pump is blood that is trapped by a shortage of outflow -- and, worse, if we are not getting those nutrients from that increase in arteriol flow to the cell -- all it is left with is the used up venous blood that is stuck in there.
Somehow, I doubt such a system would have survived many millions of years of natural selection.
One can see through B.S. that uses the words "science" and "research" a lot, with pubmed and a little effort/logical reasoning.
