Impaired leg vasodilation during dynamic exercise in healthy older women

The purpose of the present study was to test the hypothesis that leg blood flow responses during leg cycle ergometry are reduced with age in healthy non-estrogen-replaced women. Thirteen younger (20-27 yr) and thirteen older (61-71 yr) normotensive, non-endurance-trained women performed both graded and constant-load bouts of leg cycling at the same absolute exercise intensities. Leg blood flow (femoral vein thermodilution), mean arterial pressure (MAP; radial artery), mean femoral venous pressure, cardiac output (acetylene rebreathing), and blood O2 contents were measured. Leg blood flow responses at light workloads (20-40 W) were similar in younger and older women. However, at moderate workloads (50-60 W), leg blood flow responses were significantly attenuated in older women. MAP was 20-25 mmHg higher ( P < 0.01) in the older women across all work intensities, and calculated leg vascular conductance (leg blood flow/estimated leg perfusion pressure) was lower ( P < 0.05). Exercise-induced increases in leg arteriovenous O2 difference and O2 extraction were identical between groups ( P > 0.6). Leg O2 uptake was tightly correlated with leg blood flow across all workloads in both subject groups ( r2 = 0.80). These results suggest the ability of healthy older women to undergo limb vasodilation in response to submaximal exercise is impaired and that the legs are a potentially important contributor to the augmented systemic vascular resistance seen during dynamic exercise in older women.

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Reduced leg blood flow during dynamic exercise in older endurance-trained men

Journal of Applied Physiology ◽

10.1152/jappl.1998.85.1.68 ◽

1998 ◽

Vol 85 (1) ◽

pp. 68-75 ◽

Cited By ~ 153

Author(s):

David N. Proctor ◽

Peter H. Shen ◽

Niki M. Dietz ◽

Tamara J. Eickhoff ◽

Lori A. Lawler ◽

...

Keyword(s):

Blood Flow ◽

Femoral Vein ◽

Pulmonary Ventilation ◽

Hemoglobin Concentration ◽

Older Men ◽

Dynamic Exercise ◽

Whole Body ◽

Vascular Conductance ◽

Leg Blood Flow ◽

Ergometer Exercise

It is currently unclear whether aging alters the perfusion of active muscles during large-muscle dynamic exercise in humans. To study this issue, direct measurements of leg blood flow (femoral vein thermodilution) and systemic arterial pressure during submaximal cycle ergometry (70, 140, and 210 W) were compared between six younger (Y; 22–30 yr) and six older (O; 55–68 yr) chronically endurance-trained men. Whole body O2uptake, ventilation, and arterial and femoral venous samples for blood-gas, catecholamine, and lactate determinations were also obtained. Training duration (min/day), estimated leg muscle mass (dual-energy X-ray absorptiometry; Y, 21.5 ± 1.2 vs. O, 19.9 ± 0.9 kg), and blood hemoglobin concentration (Y, 14.9 ± 0.4 vs. O, 14.7 ± 0.2 g/dl) did not significantly differ ( P > 0.05) between groups. Leg blood flow, leg vascular conductance, and femoral venous O2 saturation were ∼20–30% lower in the older men at each work rate (all P < 0.05), despite similar levels of whole body O2 uptake. At 210 W, leg norepinephrine spillover rates and femoral venous lactate concentrations were more than twofold higher in the older men. Pulmonary ventilation was also higher in the older men at 140 (+24%) and 210 (+39%) W. These results indicate that leg blood flow and vascular conductance during cycle ergometer exercise are significantly lower in older endurance-trained men in comparison to their younger counterparts. The mechanisms responsible for this phenomenon and the extent to which they operate in other groups of older subjects deserve further attention.

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Leg blood flow during submaximal cycle ergometry is not reduced in healthy older normally active men

Journal of Applied Physiology ◽

10.1152/japplphysiol.00898.2002 ◽

2003 ◽

Vol 94 (5) ◽

pp. 1859-1869 ◽

Cited By ~ 59

Author(s):

David N. Proctor ◽

Sean C. Newcomer ◽

Dennis W. Koch ◽

Khoi U. Le ◽

David A. MacLean ◽

...

Keyword(s):

Blood Flow ◽

Cardiac Output ◽

Femoral Vein ◽

Plasma Catecholamines ◽

Older Men ◽

Constant Load ◽

Cycle Ergometry ◽

Leg Blood Flow ◽

Younger Men ◽

Power Outputs

The purpose of the present study was to test the hypothesis that leg blood flow responses during submaximal cycle ergometry are reduced with age in healthy normally active men. Eleven younger (20–25 yr) and eight older (62–73 yr) normotensive, nonendurance-trained men performed both graded and constant-load bouts of leg cycling at the same absolute and relative [% of peak O2 consumption (V˙o 2 peak)] exercise intensities while leg blood flow (femoral vein thermodilution), mean arterial pressure (MAP; radial artery), cardiac output (acetylene rebreathing), blood O2 content, and plasma catecholamines were measured. Leg blood flow responses at the same absolute submaximal power outputs (20–100 W) and at a fixed systemic O2 demand (1.1 l/min) did not differ between groups ( P = 0.14–0.19), despite lower absolute levels of cardiac output in the older men ( P < 0.05). MAP at the same absolute power outputs was 8–12 mmHg higher ( P < 0.05) in the older men, but calculated leg vascular conductance responses (leg blood flow/MAP) were identical in the two groups ( P > 0.9). At the same relative intensity (60% V˙o 2 peak), leg norepinephrine spillover rates were approximately twofold higher in the older men ( P = 0.38). Exercise-induced increases in leg arterial-venous O2difference were identical between groups ( P > 0.9) because both arterial and venous O2 contents were lower in the older vs. younger men. These results suggest that the ability to augment active limb blood flow and O2 extraction during submaximal large muscle mass exercise is not impaired but is well preserved with age in healthy men who are normally active.

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Exercise-induced hyperemia is associated with knee extensor fatigability in adults with type 2 diabetes

Journal of Applied Physiology ◽

10.1152/japplphysiol.00854.2018 ◽

2019 ◽

Vol 126 (3) ◽

pp. 658-667 ◽

Cited By ~ 5

Author(s):

Jonathon W. Senefeld ◽

Jacqueline K. Limberg ◽

Kathleen M. Lukaszewicz ◽

Sandra K. Hunter

Keyword(s):

Type 2 Diabetes ◽

Blood Flow ◽

Lower Limb ◽

Contractile Function ◽

Muscle Blood Flow ◽

Knee Extensor ◽

Dynamic Exercise ◽

Extensor Muscles ◽

Exercise Induced

The aim of this study was to compare fatigability, contractile function, and blood flow to the knee extensor muscles after dynamic exercise in patients with type 2 diabetes mellitus (T2DM) and controls. The hypotheses were that patients with T2DM would demonstrate greater fatigability than controls, and greater fatigability would be associated with a lower exercise-induced increase in blood flow and greater impairments in contractile function. Patients with T2DM ( n = 15; 8 men; 62.4 ± 9.0 yr; 30.4 ± 7.7 kg/m2; 7,144 ± 3,294 steps/day) and 15 healthy control subjects (8 men, 58.4 ± 6.9 yr; 28.4 ± 4.6 kg/m2; 7,893 ± 2,323 steps/day) were matched for age, sex, body mass index, and physical activity. Fatigability was quantified as the reduction in knee extensor power during a 6-min dynamic exercise. Before and after exercise, vascular ultrasonography and electrical stimulation were used to assess skeletal muscle blood flow and contractile properties, respectively. Patients with T2DM had greater fatigability (30.0 ± 20.1% vs. 14.6 ± 19.0%, P < 0.001) and lower exercise-induced hyperemia (177 ± 90% vs. 194 ± 79%, P = 0.04) than controls but similar reductions in the electrically evoked twitch amplitude (37.6 ± 24.8% vs. 31.6 ± 30.1%, P = 0.98). Greater fatigability of the knee extensor muscles was associated with postexercise reductions in twitch amplitude ( r = 0.64, P = 0.001) and lesser exercise-induced hyperemia ( r = −0.56, P = 0.009). Patients with T2DM had greater lower-limb fatigability during dynamic exercise, which was associated with reduced contractile function and lower skeletal muscle blood flow. Thus, treatments focused on enhancing perfusion and reversing impairments in contractile function in patients with T2DM may offset lower-limb fatigability and aid in increasing exercise capacity. NEW & NOTEWORTHY Although prior studies compare patients with type 2 diabetes mellitus (T2DM) with lean controls, our study includes controls matched for age, body mass, and physical activity to more closely assess the effects of T2DM. Patients with T2DM demonstrated no impairment in macrovascular endothelial function, evidenced by similar flow-mediated dilation to controls. However, patients with T2DM had greater fatigability and reduced exercise-induced increase in blood flow (hyperemia) after a lower-limb dynamic fatiguing exercise compared with controls.

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Leg Blood Flow and &OV0312;O2 during Peak Cycle Exercise in Younger and Older Women

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000121951.10417.b5 ◽

2004 ◽

Vol 36 (4) ◽

pp. 623-631 ◽

Cited By ~ 31

Author(s):

DAVID N. PROCTOR ◽

DENNIS W. KOCH ◽

SEAN C. NEWCOMER ◽

KHOI U. LE ◽

SANDRA L. SMITHMYER ◽

...

Keyword(s):

Blood Flow ◽

Older Women ◽

Cycle Exercise ◽

Leg Blood Flow

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Oxygen Uptake And Leg Blood Flow Kinetics And The Influence Of Exercise Training In Older Women

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000274408.84320.43 ◽

2007 ◽

Vol 39 (Supplement) ◽

pp. S359

Author(s):

Liza Stathokostas ◽

John M. Kowalchuk ◽

Donald H. Paterson

Keyword(s):

Blood Flow ◽

Exercise Training ◽

Oxygen Uptake ◽

Older Women ◽

Leg Blood Flow

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Middle cerebral artery blood velocity and cerebral blood flow and O2 uptake during dynamic exercise

Journal of Applied Physiology ◽

10.1152/jappl.1993.74.1.245 ◽

1993 ◽

Vol 74 (1) ◽

pp. 245-250 ◽

Cited By ~ 111

Author(s):

P. L. Madsen ◽

B. K. Sperling ◽

T. Warming ◽

J. F. Schmidt ◽

N. H. Secher ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Middle Cerebral Artery ◽

Cerebral Artery ◽

Transcranial Doppler Sonography ◽

Dynamic Exercise ◽

Global Average ◽

Proportional Increase ◽

Exercise Induced

Results obtained by the 133Xe clearance method with external detectors and by transcranial Doppler sonography (TCD) suggest that dynamic exercise causes an increase of global average cerebral blood flow (CBF). These data are contradicted by earlier data obtained during less-well-defined conditions. To investigate this controversy, we applied the Kety-Schmidt technique to measure the global average levels of CBF and cerebral metabolic rate of oxygen (CMRO2) during rest and dynamic exercise. Simultaneously with the determination of CBF and CMRO2, we used TCD to determine mean maximal flow velocity in the middle cerebral artery (MCA Vmean). For values of CBF and MCA Vmean a correction for an observed small drop in arterial PCO2 was carried out. Baseline values for global CBF and CMRO2 were 50.7 and 3.63 ml.100 g-1.min-1, respectively. The same values were found during dynamic exercise, whereas a 22% (P < 0.0001) increase in MCA Vmean was observed. Hence, the exercise-induced increase in MCA Vmean is not a reflection of a proportional increase in CBF.

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Prostaglandin production contributes to exercise-induced vasodilation in heart failure

Journal of Applied Physiology ◽

10.1152/jappl.1997.83.6.1933 ◽

1997 ◽

Vol 83 (6) ◽

pp. 1933-1940 ◽

Cited By ~ 17

Author(s):

Chim C. Lang ◽

Don B. Chomsky ◽

Javed Butler ◽

Shiv Kapoor ◽

John R. Wilson

Keyword(s):

Heart Failure ◽

Skeletal Muscle ◽

Blood Flow ◽

Peak Exercise ◽

Prostaglandin Production ◽

Leg Blood Flow ◽

Patients With Heart Failure ◽

Prostaglandin F ◽

Exercise Induced ◽

Arteriolar Vasodilation

Lang, Chim C., Don B. Chomsky, Javed Butler, Shiv Kapoor, and John R. Wilson. Prostaglandin production contributes to exercise-induced vasodilation in heart failure. J. Appl. Physiol. 83(6): 1933–1940, 1997.—Endothelial release of prostaglandins may contribute to exercise-induced skeletal muscle arteriolar vasodilation in patients with heart failure. To test this hypothesis, we examined the effect of indomethacin on leg circulation and metabolism in eight chronic heart failure patients, aged 55 ± 4 yr. Central hemodynamics and leg blood flow, determined by thermodilution, and leg metabolic parameters were measured during maximum treadmill exercise before and 2 h after oral administration of indomethacin (75 mg). Leg release of 6-ketoprostaglandin F1α was also measured. During control exercise, leg blood flow increased from 0.34 ± 0.03 to 1.99 ± 0.19 l/min ( P < 0.001), leg O2 consumption from 13.6 ± 1.8 to 164.5 ± 16.2 ml/min ( P < 0.001), and leg prostanoid release from 54.1 ± 8.5 to 267.4 ± 35.8 pg/min ( P < 0.001). Indomethacin suppressed release of prostaglandin F1α( P < 0.001) throughout exercise and decreased leg blood flow during exercise ( P < 0.05). This was associated with a corresponding decrease in leg O2 consumption ( P < 0.05) and a higher level of femoral venous lactate at peak exercise ( P < 0.01). These data suggest that release of vasodilatory prostaglandins contributes to skeletal muscle arteriolar vasodilation in patients with heart failure.

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Does endothelin-1 participate in the exercise-induced changes of blood flow distribution of muscles in humans?

Journal of Applied Physiology ◽

10.1152/jappl.1997.82.4.1107 ◽

1997 ◽

Vol 82 (4) ◽

pp. 1107-1111 ◽

Cited By ~ 49

Author(s):

Seiji Maeda ◽

Takashi Miyauchi ◽

Michiko Sakane ◽

Makoto Saito ◽

Shinichi Maki ◽

...

Keyword(s):

Blood Flow ◽

Femoral Vein ◽

Plasma Concentrations ◽

Flow Distribution ◽

Plasma Norepinephrine ◽

Blood Flow Distribution ◽

Endothelin 1 ◽

Ergometer Exercise ◽

Exercise Induced ◽

Induced Changes

Maeda, Seiji, Takashi Miyauchi, Michiko Sakane, Makoto Saito, Shinichi Maki, Katsutoshi Goto, and Mitsuo Matsuda. Does endothelin-1 participate in the exercise-induced changes of blood flow distribution of muscles in humans? J. Appl. Physiol. 82(4): 1107–1111, 1997.—Endothelin-1 (ET-1) is an endothelium-derived potent vasoconstrictor peptide that potentiates contractions to norepinephrine in human vessels. We previously reported that the circulating plasma concentration of ET-1 is significantly increased after exercise (S. Maeda, T. Miyauchi, K. Goto, and M. Matsuda. J. Appl. Physiol. 77: 1399–1402, 1994). To study the roles of ET-1 during and after exercise, we investigated whether endurance exercise affects the production of ET-1 in the circulation of working muscles and nonworking muscles. Male athletes performed one-leg cycle ergometer exercise of 30-min duration at intensity of 110% of their individual ventilatory threshold. Plasma concentrations of ET-1 in both sides of femoral veins (veins in the working leg and nonworking leg) and in the femoral artery (artery in the nonworking leg) were measured before and after exercise. The plasma ET-1 concentration in the femoral vein in the nonworking leg was significantly increased after exercise, whereas that in femoral vein in the working leg was not changed. The arteriovenous difference in ET-1 concentration was significantly increased after exercise in the circulation of the nonworking leg but not of the working leg, which suggests that the production of ET-1 was increased in the circulation of the nonworking leg by exercise. The present study also demonstrated that the plasma norepinephrine concentrations were elevated by exercise in the femoral veins of both the working and nonworking legs, suggesting that the sympathetic nerve activity was augmented in both legs during exercise. Therefore, the present study demonstrates the possibility that the increase in production of ET-1 in nonworking muscles may cause vasoconstriction and hence decrease blood flow in nonworking muscles through its direct vasoconstrictive action or through an indirect effect of ET-1 to enhance vasoconstrictions to norepinephrine and that these responses may be helpful in increasing blood flow in working muscles. We propose that endogenous ET-1 contributes to the exercise-induced redistribution of blood flow in muscles.

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Determination of Leg Blood Flow During Exercise in Man: An Indicator-Dilution Technique Based on Femoral Venous Dye Infusion

Clinical Science ◽

10.1042/cs0450135 ◽

1973 ◽

Vol 45 (2) ◽

pp. 135-146 ◽

Cited By ~ 5

Author(s):

J. Wahren ◽

L. Jorfeldt

Keyword(s):

Blood Flow ◽

Healthy Subjects ◽

Femoral Vein ◽

Indicator Dilution ◽

Dilution Method ◽

Dilution Technique ◽

Flow Measurements ◽

Leg Blood Flow ◽

Indicator Dilution Technique

1. A dye-dilution method has been developed for the determination of leg blood flow in man. The method is based on the infusion of indicator into the distal part of the femoral vein with blood sampling from the same vein at the level of the inguinal ligament. Catheterization of the femoral artery is not required. Evidence of adequate mixing of dye and blood is presented, based on the finding of the same dye concentration in samples from two different levels in the femoral vein. 2. Leg blood flow measured by this technique at rest and during exercise in six healthy subjects was found to agree closely with simultaneous determinations with an intra-arterial indicator-dilution technique. The reproducibility of the blood-flow measurements, expressed as the coefficient of variation for a single determination, was 9·8%. 3. A routine procedure is suggested for leg blood-flow determination based on femoral venous dye infusion. Using this procedure, leg blood flow was measured in twelve healthy subjects at rest and during exercise at work loads of 100, 200, 400 and 600 kpm/min. A linear relationship was found between leg blood flow and pulmonary oxygen uptake. 4. The applicability of this method to the study of patients with occlusive arterial disease of the leg is illustrated by findings in two patients before and after vascular reconstruction.

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