β-Adrenergic receptor number in human lymphocytes is inversely correlated with aerobic capacity

1998 ◽  
Vol 274 (6) ◽  
pp. E1106-E1112 ◽  
Author(s):  
Nobuharu Fujii ◽  
Sachiko Homma ◽  
Fumio Yamazaki ◽  
Ryoko Sone ◽  
Takeshi Shibata ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Aerobic Capacity ◽  
Adrenergic Receptor ◽  
Ventilatory Threshold ◽  
Human Lymphocytes ◽  
Mrna Level ◽  
Maximal Oxygen Consumption ◽  
Subsequent Degradation ◽  
Intracellular Compartments ◽  
Model Cell

In the present study, the relationships between β-adrenergic receptor (β-AR) expression and aerobic capacity evaluated by maximal oxygen consumption ([Formula: see text]) and oxygen consumption level at ventilatory threshold (V˙o 2@VT) were investigated. Seventeen physically untrained and 25 trained men participated in the study. After supine resting, the peripheral blood was sampled for preparation of lymphocytes, the model cell used to analyze the β-AR state. The total number of β-AR in lymphocytes (β-ARtotal) was inversely correlated with theV˙o 2 max( r = −0.368; P < 0.05) and theV˙o 2@VT ( r = −0.359; P < 0.05). Similar relationships were also observed between the number of β-AR in cell surface and both V˙o 2 max( r = −0.491; P < 0.05) andV˙o 2@VT ( r = −0.498; P < 0.05). However, no correlation was obtained between the number of β-AR in intracellular compartments and eitherV˙o 2 max orV˙o 2@VT. The β2-AR mRNA level quantified by the use of competitive reverse transcription-polymerase chain reaction was inversely correlated withV˙o 2@VT ( r = −0.567; P < 0.05) and positively correlated with β-ARtotal( r = 0.521; P < 0.05). These findings suggest that the β-AR number in lymphocytes is inversely correlated with aerobic capacity. This relationship may be explained by downregulation of β-AR, including internalization with subsequent degradation of the receptors and inhibition of the β-AR biosynthesis.

scholarly journals Aerobic capacity and respiratory patterns are better in recreational basketball-engaged university students than age-matched untrained males

2021 ◽  
Vol 13 (1) ◽  
pp. 111-120
Author(s):  
Mladen Mikić ◽  
Marko D.M. Stojanović ◽  
Aleksandra Milovančev ◽  
Tatjana Miljković ◽  
Marija Bjelobrk ◽  
...  
Keyword(s):  
Body Weight ◽  
Oxygen Consumption ◽  
University Students ◽  
Aerobic Capacity ◽  
Ventilatory Threshold ◽  
Maximal Oxygen Consumption ◽  
Body Height ◽  
Time To Exhaustion ◽  
Respiratory Parameters ◽  
Recreational Basketball

Abstract Study aim: To asses and compare the aerobic capacity and respiratory parameters in recreational basketball-engaged university students with age-matched untrained young adults. Material and methods: A total of 30 subjects were selected to took part in the study based on recreational-basketball activity level and were assigned to a basketball (BG: n = 15, age 22.86 ± 1.35 yrs., body height 185.07 ± 5.95 cm, body weight 81.21 ± 6.15 kg) and untrained group (UG: n = 15, age 22.60 ± 1.50 yrs., body height 181.53 ± 6.11 cm, body weight 76.89 ± 7.30 kg). Inspiratory vital capacity (IVC), forced expiration volume (FEV1), FEV1/IVC ratio, maximal oxygen consumption (VO2max), ventilatory threshold (VO2VT) and time to exhaustion, were measured in all subjects. Student T-test for independent Sample and Cohen’s d as the measure of the effect size were calculated. Results: Recreational basketball-engaged students (EG) reached significantly greater IVC (t = 7.240, p < 0.001, d = 1.854), FEV1 (t = 10.852, p < 0.001, d = 2.834), FEV1/IVC ratio (t = 6.370, p < 0.001, d = 3.920), maximal oxygen consumption (t = 9.039, p < 0.001, d = 3.310), ventilatory threshold (t = 9.859, p < 0.001, d = 3.607) and time to exhaustion (t = 12.361, p < 0.001, d = 4.515) compared to UG. Conclusions: Long-term exposure to recreational basketball leads to adaptive changes in aerobic and respiratory parameters in male university students.

Peak Oxygen Consumption and Ventilatory Thresholds on Six Modes of Exercise

1996 ◽  
Vol 21 (2) ◽  
pp. 79-89 ◽  
Author(s):  
Thomas D. Smith ◽  
Tom R. Thomas ◽  
Ben R. Londeree ◽  
Qiang Zhang ◽  
George Ziogas
Keyword(s):  
Oxygen Consumption ◽  
Key Words ◽  
Aerobic Capacity ◽  
Lactate Threshold ◽  
Ventilatory Threshold ◽  
Maximal Oxygen Consumption ◽  
The Other ◽  
Peak Oxygen Consumption ◽  
Capacity Measure ◽  
Post Hoc

In order to compare responses on six modes of exercise for maximal oxygen consumption [Formula: see text] and ventilatory thresholds (VT-I, VT-2), 10 male recreational exercisers (23 ± 3 yrs) completed incremental maximal tests on treadmill, stationary skier, shuffle skier, stepper, stationary cycle, and rower. After extensive habituation, [Formula: see text], VT-1, and VT-2 were determined during each maximal bout. A MANOVA followed by ANOVAs, Tukey post hoc tests, and noncentral F tests indicated that the treadmill elicited a significantly higher peak oxygen consumption than did the other modes, and the skier and stepper values were higher than the rower. [Formula: see text] at VT-1 was higher on the treadmill than cycle. The treadmill also elicited a higher [Formula: see text] at VT-2 than the shuffle skier, cycle, and rower. However, no differences were observed among modes for VT-1 and VT-2 when expressed as a percentage of [Formula: see text]. These results suggest that the treadmill elicits a higher aerobic capacity measure than other modes, but the ventilatory threshold responses [Formula: see text] are similar among modes. Key words: exercise mode, aerobic capacity, lactate threshold

scholarly journals Exercise-induced changes in β-adrenergic-receptor mRNA level measured by competitive RT-PCR

1997 ◽  
Vol 82 (6) ◽  
pp. 1926-1931 ◽  
Author(s):  
Nobuharu Fujii ◽  
Takeshi Shibata ◽  
Sachiko Homma ◽  
Haruo Ikegami ◽  
Kazuo Murakami ◽  
...  
Keyword(s):  
Adrenergic Receptor ◽  
Human Lymphocytes ◽  
Mrna Level ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Receptor Mrna ◽  
Exercise Induced ◽  
Induced Changes ◽  
Receptor Mrna Level

Fujii, Nobuharu, Takeshi Shibata, Sachiko Homma, Haruo Ikegami, Kazuo Murakami, and Hitoshi Miyazaki. Exercise-induced changes in β-adrenergic-receptor mRNA level measured by competitive RT-PCR. J. Appl. Physiol. 82(6): 1926–1931, 1997.—Competitive reverse transcription-polymerase chain reaction (RT-PCR) analysis was used to clarify whether dynamic exercise-induced increases in β-adrenergic-receptor (β-AR) number in human lymphocytes are accompanied by increases in the β-AR mRNA level. Sixteen healthy subjects performed cycle ergometry until exhaustion. Before and immediately after exercise, peripheral blood was drawn from a forearm vein for preparation of lymphocytes. Both the β-AR mRNA level and the β-AR number were significantly increased by exercise. The changes in β-AR mRNA level and β-AR number were significantly correlated ( r = 0.63, P < 0.01). This finding suggests that a rapid increase in β-AR mRNA level might be an early adaptive response of the sympathetic nervous system to dynamic exercise. In vitro incubation of lymphocytes with epinephrine had no effect on β-AR mRNA levels, nor did adenosine 3′,5′-cyclic monophosphate, protein kinase C, or intracellular Ca2+ increase the β-AR mRNA level in vitro. Therefore, it appears that other mechanisms underlie the exercise-induced elevation of β-AR mRNA levels in human lymphocytes.

COMPARISON OF LACTATE AND VENTILATORY THRESHOLD TO MAXIMAL OXYGEN CONSUMPTION: A META-ANALYSIS 402

1996 ◽  
Vol 28 (Supplement) ◽  
pp. 68
Author(s):  
F. B. Wyatt ◽  
Z. V. Tran ◽  
C. G. Jackson ◽  
R. J. Brustad ◽  
N. Banchero
Keyword(s):  
Oxygen Consumption ◽  
Ventilatory Threshold ◽  
Meta Analysis ◽  
Maximal Oxygen Consumption

scholarly journals Increasing Iron Status through Dietary Supplementation in Iron-Depleted, Sedentary Women Increases Endurance Performance at Both Near-Maximal and Submaximal Exercise Intensities

2019 ◽  
Vol 149 (2) ◽  
pp. 231-239 ◽  
Author(s):  
Laura M Pompano ◽  
Jere D Haas
Keyword(s):  
Oxygen Consumption ◽  
Aerobic Exercise ◽  
Physical Performance ◽  
Iron Supplementation ◽  
Aerobic Training ◽  
Ventilatory Threshold ◽  
Iron Status ◽  
Maximal Oxygen Consumption ◽  
Endurance Performance ◽  
Mean Difference

ABSTRACT Background Iron deficiency persists as the most common micronutrient deficiency globally, despite having known detrimental effects on physical performance. Although iron supplementation and aerobic exercise have been examined individually and are known to improve physical performance, the impact of simultaneous iron supplementation and aerobic training remains unclear. Objective The aim of this study was to examine the individual and combined effects of iron supplementation and aerobic training on improving maximal and submaximal physical performance in iron-depleted, nonanemic (IDNA) women. We hypothesized that women receiving iron would improve their endurance performance but not their estimated maximal oxygen consumption (eVO2max). Methods Seventy-three sedentary, previously untrained IDNA (serum ferritin <25 µg/L and hemoglobin >110 g/L) women aged 18–26 y with a body mass index (kg/m2) of 17–25 participated in a double-blind, 8-wk, randomized controlled trial with a 2 × 2 factorial design including iron supplementation (42 mg elemental Fe/d) or placebo and aerobic exercise training (5 d/wk for 25 min at 75–85% of age-predicted maximum heart rate) or no training. Linear models were used to examine relations between training, supplement, and changes in the primary outcomes of observed maximal oxygen consumption (VO2peak) and eVO2max and ventilatory threshold (absolute oxygen consumption and percentage of maximum). Re-evaluation of a published meta-analysis was used to compare effects of iron supplementation on maximal oxygen consumption (VO2max) and VO2peak. Results There were significant training-by-supplement interactions for VO2peak, volume of oxygen consumption at the ventilatory threshold, and the percentage of eVO2max where the threshold occurred, with the iron-untrained group performing better than the placebo-untrained group. There was no beneficial effect of iron supplementation for VO2max (mean difference: 0.53; 95% CI: −0.75, 1.81; P = 0.42), but a significant benefit was observed for VO2peak (mean difference: 1.87; 95% CI: 0.15, 3.60; P = 0.03). Conclusions Iron supplementation increases endurance performance at submaximal and maximal (VO2peak) exercise intensities in IDNA women. However, increasing iron status does not increase eVO2max. This trial was registered at clinicaltrials.gov as NCT03002090.

The “Talk Test” is a practical tool to determine aerobic training zones in overweight and obese patients.

2020 ◽  
Author(s):  
Ignacio Orizola-Cáceres ◽  
Hugo Cerda-Kohler ◽  
Carlos Burgos-Jara ◽  
Roberto Meneses-Valdes ◽  
Rafael Gutierrez-Pino ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Power Output ◽  
Aerobic Training ◽  
Exercise Prescription ◽  
Ventilatory Threshold ◽  
Maximal Oxygen Consumption ◽  
Mean Difference ◽  
Obese Patients ◽  
Analog Scale ◽  
Practical Tool

Abstract Background: to validate the traditional talk test (TTT) and an alternative talk test (ATT; using a visual analog scale) in overweight/obese (OW-OB) patients and to establish its accuracy in determining the aerobic training zones.Methods: We recruited 19 subjects aged 34.9 ± 6.7 years, diagnosed with overweight/obesity (BMI 31.8 ± 5.7). Every subject underwent incremental cycloergometric tests for maximal oxygen consumption, and TT in a randomized order. At the end of each stage during the TT each subject read out loud a 40 words text and then had to identify the comfort to talk in two modalities: TTT which consisted in answering “Yes”, “I don’t know” or “No” to the question Was talking comfortable?, or ATT through a 1 to 10 numeric perception scale (visual scale analog: VAS). The magnitude of differences was interpreted in comparison to the smallest worthwhile change (SWC) and was used to determine agreement.Results: Agreement between the power output at the VAS 2-3 of ATT and the power output at the ventilatory threshold 1 (very likely equivalent; mean difference -1.3 W, 90 % CL (-8.2; 5.6), % chances for higher/similar/lower values of 0.7/99.1/0.2 %). Also, there was an agreement between the power output at the VAS 6-7 of ATT and the power output at the ventilatory threshold 2 (very likely equivalent; mean difference 11.1 W, 90 % CL (2.8; 19.2), % chances for higher/similar/lower values of 0.0/97.6/2.4 %). Conclusions: ATT is a tool to determine exercise intensity and to establish aerobic training zones for exercise prescription in OW-OB patients.

Running economy and its correlation to performance and fitness variables in recreationally-trained distance runners

2020 ◽  
Vol 16 (2) ◽  
pp. 107-112 ◽  
Author(s):  
B.N. Bozzini ◽  
J.K. Pellegrino ◽  
A.J. Walker ◽  
B.A. McFadden ◽  
A.N. Poyssick ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Ventilatory Threshold ◽  
Maximal Oxygen Consumption ◽  
Time Trial ◽  
Running Economy ◽  
Distance Runners ◽  
Fat Percentage ◽  
Long Distance ◽  
Significant Relationships ◽  
Physiological Capacity

Specific physiological attributes such as maximal oxygen consumption (VO2max) and running economy (RE) have been suggested to help predict long distance performance in endurance athletes. Despite this, investigations of RE have yielded conflicting results, particularly when comparing elite and recreational runners. The purpose of this study was to illustrate correlations between RE, expressed as submaximal oxygen consumption at a given speed, and time trial (TT) performance in addition to various fitness markers in endurance-trained individuals. Trained distance runners (n=21) performed a battery of tests over three sessions to provide measurements of RE at 2.68 m/s (RE2.68) and 4.25 m/s (RE4.25), TT performance, VO2max, velocity at ventilatory threshold (VVT), and body composition. Pearson-product moment correlations, defined as weak (r≥0.25), moderate (r≥0.45), and strong (r≥0.65), were calculated among all measures and significance was set at P<0.05. The findings suggested that faster TT performance was significantly (P<0.05) correlated to a higher VO2max (r=-0.86) and lower body fat percentage (BF%; r=0.78). However, TT performance displayed only a weak trend to RE4.25 (r=-0.40, P=0.07) and was not correlated to RE2.68 (r=0.15; P>0.05). Additionally, better RE4.25 (i.e. decreased submaximal oxygen consumption) was associated with a lower VO2max (r=0.66, P<0.05) and an increased BF% (r=-0.46, P<0.05). RE2.68 revealed no significant relationships with these measures. Comparable to their elite counterparts, higher aerobic capacity is strongly linked to performance in recreational distance runners, though in this cohort RE only weakly related to performance at the faster velocity. Finally, the inverse relationship between markers of overall fitness and RE suggests that enhanced RE may be an adaptive response to a limited physiological capacity in this population.

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