To determine the effects of pre-sleep supplementation with a novel low glycemic index (LGI) carbo... more To determine the effects of pre-sleep supplementation with a novel low glycemic index (LGI) carbohydrate (CHO) on next-morning substrate utilization, gastrointestinal distress (GID), and endurance running performance (5-km time-trial, TT). Using a double-blind, randomized, placebo (PLA) controlled, crossover design, trained participants (n = 14; 28 ± 9 years, 8/6 male/female, 55 ± 7 mL/kg/min) consumed a LGI, high glycemic index (HGI), or 0 kcal PLA supplement ≥ 2 h after their last meal and <30 min prior to sleep. Upon arrival, resting energy expenditure (REE), substrate utilization, blood glucose, satiety, and GID were assessed. An incremental exercise test (IET) was performed at 55, 65, and 75% peak volume of oxygen consumption (VO2peak) with GID, rating of perceived exertion (RPE) and substrate utilization recorded each stage. Finally, participants completed the 5-km TT. There were no differences in any baseline measure. During IET, CHO utilization tended to be greater with L...
This study sought to determine whether afferent feedback associated with peripheral muscle fatigu... more This study sought to determine whether afferent feedback associated with peripheral muscle fatigue inhibits central motor drive (CMD) and thereby limits endurance exercise performance. On two separate days, eight men performed constant-load, single-leg knee extensor exercise to exhaustion (85% of peak power) with each leg (Leg1 and Leg2). On another day, the performance test was repeated with one leg (Leg1) and consecutively (within 10 s) with the other/contralateral leg (Leg2-post). Exercise-induced quadriceps fatigue was assessed by reductions in potentiated quadriceps twitch-force from pre- to postexercise (ΔQtw,pot) in response to supramaximal magnetic femoral nerve stimulation. The output from spinal motoneurons, estimated from quadriceps electromyography (iEMG), was used to reflect changes in CMD. Rating of perceived exertion (RPE) was recorded during exercise. Time to exhaustion (∼9.3 min) and exercise-induced ΔQtw,pot (∼51%) were similar in Leg1 and Leg2 ( P > 0.5). In th...
Objective-To better understand the hemodynamic and autonomic reflex abnormalities in heartfailure... more Objective-To better understand the hemodynamic and autonomic reflex abnormalities in heartfailure patients (HF), we investigated the influence of group III/IV muscle afferents on their cardiovascular response to rhythmic exercise. Methods-Nine HF-patients (NYHA class-II, mean left ventricular ejection-fraction: 27±3%) performed single leg knee-extensor exercise (25/50/80% peak-workload) under control conditions and with lumbar intrathecal fentanyl impairing μ-opioid receptor-sensitive muscle afferents. Results-Cardiac-output (Q) and femoral blood-flow (Q L) were determined, and arterial/venous blood samples collected at each workload. Exercise-induced fatigue was estimated via pre/postexercise changes in quadriceps strength. There were no hemodynamic differences between conditions at rest. During exercise, Q was 8-13% lower with Fentanyl-blockade, secondary to significant reductions in stroke volume and heart rate. Lower norepinephrine spillover during exercise with Fentanyl revealed an attenuated sympathetic outflow that likely contributed to the 25% increase in leg vascular conductance (p<0.05). Despite a concomitant 4% reduction in blood pressure, Q L was 10-14% higher and end-exercise fatigue attenuated by 30% with Fentanylblockade (p<0.05). Conclusion/Practice/Implications-Although group III/IV muscle afferents play a critical role for central hemodynamics in HF-patients, it also appears that these sensory neurons cause
Graded exercise results not only in the modulation of adrenergic mediated smooth muscle tone and ... more Graded exercise results not only in the modulation of adrenergic mediated smooth muscle tone and a preferential increase in blood flow to the active skeletal muscle termed "functional sympatholysis", but is also paralleled by metabolically-induced reductions in pH. Therefore, we sought to determine if pH attenuates α 1-adrenergic receptor sensitivity in human feed arteries. Feed arteries (560±31 µm ID) were harvested from 24 humans (55±4 yrs) and studied using the isometric tension technique. Vessel function was assessed using potassium chloride (KCl), phenylephrine (PE), acetylcholine (ACh), and sodium nitroprusside (SNP) concentration response curves (CRCs) to characterize non-receptor and receptor-mediated vasocontraction as well as endothelium-dependent and independent vasorelaxation, respectively. All CRCs were conducted on, originally contiguous, vessel rings in separate baths with a pH of: 7.4, 7.1, 6.8, or 6.5. Reducing pH, via HCl, reduced maximal PE-induced vasocontraction (pH 7.4 = 85 ± 19; 7.1= 57 ± 16; 6.8 = 34 ± 15; 6.5 = 16 ± 5 %KCl max), which was partially due to reduced smooth muscle function, as assessed by KCl, (pH 7.4 = 88 ± 13; 7.1= 67 ± 8; 6.8= 67 ± 9; 6.5= 58 ± 8 %KCl max). Graded acidosis had no effect on maximal vasorelaxation. In summary, these data reveal that reductions in extracellular pH attenuate α 1-mediated vasocontraction, which is partially explained by reduced smooth muscle function, although vasorelaxation to ACh and SNP remained intact. These findings support the concept that local acidosis likely contributes to functional sympatholysis and exercise hyperemia by opposing sympathetically-mediated vasoconstriction while not impacting vasodilation.
American Journal of Physiology-Heart and Circulatory Physiology, 2011
This study used alterations in body position to identify differences in hemodynamic responses to ... more This study used alterations in body position to identify differences in hemodynamic responses to passive exercise. Central and peripheral hemodynamics were noninvasively measured during 2 min of passive knee extension in 14 subjects, whereas perfusion pressure (PP) was directly measured in a subset of 6 subjects. Movement-induced increases in leg blood flow (LBF) and leg vascular conductance (LVC) were more than twofold greater in the upright compared with supine positions (LBF, supine: 462 ± 6, and upright: 1,084 ± 159 ml/min, P < 0.001; and LVC, supine: 5.3 ± 1.2, and upright: 11.8 ± 2.8 ml·min−1·mmHg−1, P < 0.002). The change in heart rate (HR) from baseline to peak was not different between positions (supine: 8 ± 1, and upright: 10 ± 1 beats/min, P = 0.22); however, the elevated HR was maintained for a longer duration when upright. Stroke volume contributed to the increase in cardiac output (CO) during the upright movement only. CO increased in both positions; however, the...
American Journal of Physiology-Heart and Circulatory Physiology, 2012
This study sought to characterize the role of free radicals in regulating central and peripheral ... more This study sought to characterize the role of free radicals in regulating central and peripheral hemodynamics at rest and during exercise in patients with heart failure (HF). We examined cardiovascular responses to dynamic handgrip exercise (4, 8, and 12 kg at 1 Hz) following consumption of either a placebo or acute oral antioxidant cocktail (AOC) consisting of vitamin C, E, and α-lipoic acid in a balanced, crossover design. Central and peripheral hemodynamics, mean arterial pressure, cardiac index, systemic vascular resistance (SVR), brachial artery blood flow, and peripheral (arm) vascular resistance (PVR) were determined in 10 HF patients and 10 age-matched controls. Blood assays evaluated markers of oxidative stress and efficacy of the AOC. When compared with controls, patients with HF exhibited greater oxidative stress, measured by malondialdehyde (+36%), and evidence of endogenous antioxidant compensation, measured by greater superoxide dismutase activity (+83%). The AOC incre...
A spinal cord injury (SCI) clearly results in greater cardiovascular risk; however, accompanying ... more A spinal cord injury (SCI) clearly results in greater cardiovascular risk; however, accompanying changes in peripheral vascular structure below the lesion mean that the real impact of a SCI on vascular function is unclear. Therefore, utilizing passive leg movement-induced (PLM) hyperaemia, an index of nitric oxide (NO)-dependent vascular function and the central hemodynamic response to this intervention, we studied eight individuals with a SCI and eight age-matched controls (CTRL). Specifically, we assessed heart rate (HR), stroke volume (SV), cardiac output (CO), mean arterial pressure (MAP), leg blood flow (LBF) and thigh composition. In CTRL, passive movement transiently decreased MAP and increased HR and CO from baseline by 2.5 ± 1 mmHg, 7 ± 2 bpm and 0.5 ± 0.1 L min(-1) respectively. In SCI, HR and CO responses were unidentifiable. LBF increased to a greater extent in CTRL (515 ± 41 ∆mL min(-1)) compared with SCI, (126 ± 25 ∆mL min(-1)) (P &lt; 0.05). There was a strong relationship between ∆LBF and thigh muscle volume (r = 0.95). After normalizing ∆LBF for this strong relationship (∆LBF/muscle volume), there was evidence of preserved vascular function in SCI (CTRL: 120 ± 9; SCI 104 ± 11 mL min(-1) L(-1)). A comparison of ∆LBF in the passively moved and stationary leg, to partition the contribution of the blood flow response, implied that 35% of the hyperaemia resulted from cardioacceleration in the CTRL, whereas all the hyperaemia appeared peripheral in origin in the SCI. Thus, utilizing PLM-induced hyperaemia as marker of vascular function, it is evident that peripheral vascular impairment is not an obligatory accompaniment to a SCI.
Passive leg movement (PLM) and static stretching (SS) likely activate the mechanoreflex, elicitin... more Passive leg movement (PLM) and static stretching (SS) likely activate the mechanoreflex, eliciting cardiovascular responses, though comparative study is lacking. Hyperoxia elevates free radicals (FR), though it remains to be seen, if acute elevations in FR alters the mechanoreflex, and if sex may alter this response. PURPOSE: to directly compare the central and peripheral hemodynamic responses to SS and PLM, after normoxic (FiO2 0.21) and hyperoxic (FiO2 1.0) exposure in males and females. METHODS: In a single-blind design, 23 young healthy females (F, n=12) and males (M, n=11) inspired normoxic or hyperoxic gas for 10 min, prior to PLM (knee flexion-extension) or SS (ankle dorsiflexion). Central hemodynamics (cardiac output [CO], stroke volume [SV], and HR), were measured using a Finometer, while a near-infrared spectrometer (NIRS) assessed the microvascular response (tissue oxygen saturation, StO2%) on the vastus lateralis. RESULTS: Baseline central or peripheral hemodynamics were not different for PLM and SS (p<0.05). Though both methods induced HR driven increases in CO, the PLM responses were greater (ΔHR: 15.0±9.5 vs 8.6±8.1 bpm, ΔCO: 1.3± 0.8 vs. 0.8±0.7 L/min, p<0.05). Peripherally, PLM increased StO2 from baseline, while SS decreased StO2 (ΔStO2: 2.8±2.5 vs.-1.3±1.1%, p<0.05). Regarding sex, no differences were observed at baseline (p>0.05), but in response to PLM, males exhibited a greater CO response greater (ΔCO: 1.7±0.7 vs. 0.9±0.6 L/min, p<0.05). Peripherally, PLM increased StO2 from baseline for both sexes (p<0.05), though there was a significant difference in the peripheral response to PLM between the sexes (M: 4.2±2.0 vs F: 2.3±2.7 ΔStO2%, p<0.05). Hyperoxia had no effect on CO at baseline (p>0.05), or the response to PLM, though the sex difference persisted (ΔCO: 1.8 ± 1.0 vs 1.1 ± 0.6 L/min, M v. F, p<0.05). Hyperoxia increased StO2, but the response to PLM was unaffected, though the sex specificity remained (M: 4.5±1.8 vs F: 2.1±2.7 ΔStO2%, p<0.05). CONCLUSION: The present study directly compared two methods of evoking the mechanoreflex, which appear disparate, though unaffected by hyperoxia. Females exhibit an attenuated mechanoreflex, though, unlike the macrovascular responses to PLM which have been reported to be similar between sexes, the microvascular responses to PLM may differ.
Introduction: Orthostatic intolerance (OI) is the inability of the cardiovascular system to adequ... more Introduction: Orthostatic intolerance (OI) is the inability of the cardiovascular system to adequately adjust to gravity upon standing, resulting in lightheadedness or syncope. OI can be characteristic of pathology (e.g. postural orthostatic tachycardia syndrome), which disproportionately affect women, and is compounded by inactivity. Thus, we tested the effects of remotely supervised home-based, 4-week resistance training (RT) program vs. control on the orthostatic stress response of previously inactive young females using the NASA Lean Test (NLT). Methods: Systolic (SBP) and diastolic (DBP) blood pressures, and heart rate (HR) were assessed during the NLT, pre- and post-training, along with fitness and body composition in females randomized to RT or control (n=7). Results: RT improved fitness (group*intervention, p=0.047) and fat-mass (-3.4±2.9 vs. +0.3±0.7Δlbs, p=0.037) over control. The NLT significantly altered SBP, DBP, and HR (all, p<0.01). For SBP, the interaction of gro...
To determine the effects of pre-sleep supplementation with a novel low glycemic index (LGI) carbo... more To determine the effects of pre-sleep supplementation with a novel low glycemic index (LGI) carbohydrate (CHO) on next-morning substrate utilization, gastrointestinal distress (GID), and endurance running performance (5-km time-trial, TT). Using a double-blind, randomized, placebo (PLA) controlled, crossover design, trained participants (n = 14; 28 ± 9 years, 8/6 male/female, 55 ± 7 mL/kg/min) consumed a LGI, high glycemic index (HGI), or 0 kcal PLA supplement ≥ 2 h after their last meal and <30 min prior to sleep. Upon arrival, resting energy expenditure (REE), substrate utilization, blood glucose, satiety, and GID were assessed. An incremental exercise test (IET) was performed at 55, 65, and 75% peak volume of oxygen consumption (VO2peak) with GID, rating of perceived exertion (RPE) and substrate utilization recorded each stage. Finally, participants completed the 5-km TT. There were no differences in any baseline measure. During IET, CHO utilization tended to be greater with L...
This study sought to determine whether afferent feedback associated with peripheral muscle fatigu... more This study sought to determine whether afferent feedback associated with peripheral muscle fatigue inhibits central motor drive (CMD) and thereby limits endurance exercise performance. On two separate days, eight men performed constant-load, single-leg knee extensor exercise to exhaustion (85% of peak power) with each leg (Leg1 and Leg2). On another day, the performance test was repeated with one leg (Leg1) and consecutively (within 10 s) with the other/contralateral leg (Leg2-post). Exercise-induced quadriceps fatigue was assessed by reductions in potentiated quadriceps twitch-force from pre- to postexercise (ΔQtw,pot) in response to supramaximal magnetic femoral nerve stimulation. The output from spinal motoneurons, estimated from quadriceps electromyography (iEMG), was used to reflect changes in CMD. Rating of perceived exertion (RPE) was recorded during exercise. Time to exhaustion (∼9.3 min) and exercise-induced ΔQtw,pot (∼51%) were similar in Leg1 and Leg2 ( P > 0.5). In th...
Objective-To better understand the hemodynamic and autonomic reflex abnormalities in heartfailure... more Objective-To better understand the hemodynamic and autonomic reflex abnormalities in heartfailure patients (HF), we investigated the influence of group III/IV muscle afferents on their cardiovascular response to rhythmic exercise. Methods-Nine HF-patients (NYHA class-II, mean left ventricular ejection-fraction: 27±3%) performed single leg knee-extensor exercise (25/50/80% peak-workload) under control conditions and with lumbar intrathecal fentanyl impairing μ-opioid receptor-sensitive muscle afferents. Results-Cardiac-output (Q) and femoral blood-flow (Q L) were determined, and arterial/venous blood samples collected at each workload. Exercise-induced fatigue was estimated via pre/postexercise changes in quadriceps strength. There were no hemodynamic differences between conditions at rest. During exercise, Q was 8-13% lower with Fentanyl-blockade, secondary to significant reductions in stroke volume and heart rate. Lower norepinephrine spillover during exercise with Fentanyl revealed an attenuated sympathetic outflow that likely contributed to the 25% increase in leg vascular conductance (p<0.05). Despite a concomitant 4% reduction in blood pressure, Q L was 10-14% higher and end-exercise fatigue attenuated by 30% with Fentanylblockade (p<0.05). Conclusion/Practice/Implications-Although group III/IV muscle afferents play a critical role for central hemodynamics in HF-patients, it also appears that these sensory neurons cause
Graded exercise results not only in the modulation of adrenergic mediated smooth muscle tone and ... more Graded exercise results not only in the modulation of adrenergic mediated smooth muscle tone and a preferential increase in blood flow to the active skeletal muscle termed "functional sympatholysis", but is also paralleled by metabolically-induced reductions in pH. Therefore, we sought to determine if pH attenuates α 1-adrenergic receptor sensitivity in human feed arteries. Feed arteries (560±31 µm ID) were harvested from 24 humans (55±4 yrs) and studied using the isometric tension technique. Vessel function was assessed using potassium chloride (KCl), phenylephrine (PE), acetylcholine (ACh), and sodium nitroprusside (SNP) concentration response curves (CRCs) to characterize non-receptor and receptor-mediated vasocontraction as well as endothelium-dependent and independent vasorelaxation, respectively. All CRCs were conducted on, originally contiguous, vessel rings in separate baths with a pH of: 7.4, 7.1, 6.8, or 6.5. Reducing pH, via HCl, reduced maximal PE-induced vasocontraction (pH 7.4 = 85 ± 19; 7.1= 57 ± 16; 6.8 = 34 ± 15; 6.5 = 16 ± 5 %KCl max), which was partially due to reduced smooth muscle function, as assessed by KCl, (pH 7.4 = 88 ± 13; 7.1= 67 ± 8; 6.8= 67 ± 9; 6.5= 58 ± 8 %KCl max). Graded acidosis had no effect on maximal vasorelaxation. In summary, these data reveal that reductions in extracellular pH attenuate α 1-mediated vasocontraction, which is partially explained by reduced smooth muscle function, although vasorelaxation to ACh and SNP remained intact. These findings support the concept that local acidosis likely contributes to functional sympatholysis and exercise hyperemia by opposing sympathetically-mediated vasoconstriction while not impacting vasodilation.
American Journal of Physiology-Heart and Circulatory Physiology, 2011
This study used alterations in body position to identify differences in hemodynamic responses to ... more This study used alterations in body position to identify differences in hemodynamic responses to passive exercise. Central and peripheral hemodynamics were noninvasively measured during 2 min of passive knee extension in 14 subjects, whereas perfusion pressure (PP) was directly measured in a subset of 6 subjects. Movement-induced increases in leg blood flow (LBF) and leg vascular conductance (LVC) were more than twofold greater in the upright compared with supine positions (LBF, supine: 462 ± 6, and upright: 1,084 ± 159 ml/min, P < 0.001; and LVC, supine: 5.3 ± 1.2, and upright: 11.8 ± 2.8 ml·min−1·mmHg−1, P < 0.002). The change in heart rate (HR) from baseline to peak was not different between positions (supine: 8 ± 1, and upright: 10 ± 1 beats/min, P = 0.22); however, the elevated HR was maintained for a longer duration when upright. Stroke volume contributed to the increase in cardiac output (CO) during the upright movement only. CO increased in both positions; however, the...
American Journal of Physiology-Heart and Circulatory Physiology, 2012
This study sought to characterize the role of free radicals in regulating central and peripheral ... more This study sought to characterize the role of free radicals in regulating central and peripheral hemodynamics at rest and during exercise in patients with heart failure (HF). We examined cardiovascular responses to dynamic handgrip exercise (4, 8, and 12 kg at 1 Hz) following consumption of either a placebo or acute oral antioxidant cocktail (AOC) consisting of vitamin C, E, and α-lipoic acid in a balanced, crossover design. Central and peripheral hemodynamics, mean arterial pressure, cardiac index, systemic vascular resistance (SVR), brachial artery blood flow, and peripheral (arm) vascular resistance (PVR) were determined in 10 HF patients and 10 age-matched controls. Blood assays evaluated markers of oxidative stress and efficacy of the AOC. When compared with controls, patients with HF exhibited greater oxidative stress, measured by malondialdehyde (+36%), and evidence of endogenous antioxidant compensation, measured by greater superoxide dismutase activity (+83%). The AOC incre...
A spinal cord injury (SCI) clearly results in greater cardiovascular risk; however, accompanying ... more A spinal cord injury (SCI) clearly results in greater cardiovascular risk; however, accompanying changes in peripheral vascular structure below the lesion mean that the real impact of a SCI on vascular function is unclear. Therefore, utilizing passive leg movement-induced (PLM) hyperaemia, an index of nitric oxide (NO)-dependent vascular function and the central hemodynamic response to this intervention, we studied eight individuals with a SCI and eight age-matched controls (CTRL). Specifically, we assessed heart rate (HR), stroke volume (SV), cardiac output (CO), mean arterial pressure (MAP), leg blood flow (LBF) and thigh composition. In CTRL, passive movement transiently decreased MAP and increased HR and CO from baseline by 2.5 ± 1 mmHg, 7 ± 2 bpm and 0.5 ± 0.1 L min(-1) respectively. In SCI, HR and CO responses were unidentifiable. LBF increased to a greater extent in CTRL (515 ± 41 ∆mL min(-1)) compared with SCI, (126 ± 25 ∆mL min(-1)) (P &lt; 0.05). There was a strong relationship between ∆LBF and thigh muscle volume (r = 0.95). After normalizing ∆LBF for this strong relationship (∆LBF/muscle volume), there was evidence of preserved vascular function in SCI (CTRL: 120 ± 9; SCI 104 ± 11 mL min(-1) L(-1)). A comparison of ∆LBF in the passively moved and stationary leg, to partition the contribution of the blood flow response, implied that 35% of the hyperaemia resulted from cardioacceleration in the CTRL, whereas all the hyperaemia appeared peripheral in origin in the SCI. Thus, utilizing PLM-induced hyperaemia as marker of vascular function, it is evident that peripheral vascular impairment is not an obligatory accompaniment to a SCI.
Passive leg movement (PLM) and static stretching (SS) likely activate the mechanoreflex, elicitin... more Passive leg movement (PLM) and static stretching (SS) likely activate the mechanoreflex, eliciting cardiovascular responses, though comparative study is lacking. Hyperoxia elevates free radicals (FR), though it remains to be seen, if acute elevations in FR alters the mechanoreflex, and if sex may alter this response. PURPOSE: to directly compare the central and peripheral hemodynamic responses to SS and PLM, after normoxic (FiO2 0.21) and hyperoxic (FiO2 1.0) exposure in males and females. METHODS: In a single-blind design, 23 young healthy females (F, n=12) and males (M, n=11) inspired normoxic or hyperoxic gas for 10 min, prior to PLM (knee flexion-extension) or SS (ankle dorsiflexion). Central hemodynamics (cardiac output [CO], stroke volume [SV], and HR), were measured using a Finometer, while a near-infrared spectrometer (NIRS) assessed the microvascular response (tissue oxygen saturation, StO2%) on the vastus lateralis. RESULTS: Baseline central or peripheral hemodynamics were not different for PLM and SS (p<0.05). Though both methods induced HR driven increases in CO, the PLM responses were greater (ΔHR: 15.0±9.5 vs 8.6±8.1 bpm, ΔCO: 1.3± 0.8 vs. 0.8±0.7 L/min, p<0.05). Peripherally, PLM increased StO2 from baseline, while SS decreased StO2 (ΔStO2: 2.8±2.5 vs.-1.3±1.1%, p<0.05). Regarding sex, no differences were observed at baseline (p>0.05), but in response to PLM, males exhibited a greater CO response greater (ΔCO: 1.7±0.7 vs. 0.9±0.6 L/min, p<0.05). Peripherally, PLM increased StO2 from baseline for both sexes (p<0.05), though there was a significant difference in the peripheral response to PLM between the sexes (M: 4.2±2.0 vs F: 2.3±2.7 ΔStO2%, p<0.05). Hyperoxia had no effect on CO at baseline (p>0.05), or the response to PLM, though the sex difference persisted (ΔCO: 1.8 ± 1.0 vs 1.1 ± 0.6 L/min, M v. F, p<0.05). Hyperoxia increased StO2, but the response to PLM was unaffected, though the sex specificity remained (M: 4.5±1.8 vs F: 2.1±2.7 ΔStO2%, p<0.05). CONCLUSION: The present study directly compared two methods of evoking the mechanoreflex, which appear disparate, though unaffected by hyperoxia. Females exhibit an attenuated mechanoreflex, though, unlike the macrovascular responses to PLM which have been reported to be similar between sexes, the microvascular responses to PLM may differ.
Introduction: Orthostatic intolerance (OI) is the inability of the cardiovascular system to adequ... more Introduction: Orthostatic intolerance (OI) is the inability of the cardiovascular system to adequately adjust to gravity upon standing, resulting in lightheadedness or syncope. OI can be characteristic of pathology (e.g. postural orthostatic tachycardia syndrome), which disproportionately affect women, and is compounded by inactivity. Thus, we tested the effects of remotely supervised home-based, 4-week resistance training (RT) program vs. control on the orthostatic stress response of previously inactive young females using the NASA Lean Test (NLT). Methods: Systolic (SBP) and diastolic (DBP) blood pressures, and heart rate (HR) were assessed during the NLT, pre- and post-training, along with fitness and body composition in females randomized to RT or control (n=7). Results: RT improved fitness (group*intervention, p=0.047) and fat-mass (-3.4±2.9 vs. +0.3±0.7Δlbs, p=0.037) over control. The NLT significantly altered SBP, DBP, and HR (all, p<0.01). For SBP, the interaction of gro...
In human arteries involved in the regulation of muscle blood flow, there is a lack of data about ... more In human arteries involved in the regulation of muscle blood flow, there is a lack of data about whether acidosis alters vascular sensitivity to vasoactive agents, as well as altering endothelium dependent vasorelaxation. Little is known about the interaction of metabolites and vascular function in human skeletal muscle feed arteries. r What is the main finding and its importance?
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