Effects ofβ-Hydroxy-β-methylbutyrate Free Acid Ingestion and Resistance Exercise on the Acute Endocrine Response

Objective. To examine the endocrine response to a bout of heavy resistance exercise following acuteβ-hydroxy-β-methylbutyrate free acid (HMB-FA) ingestion.Design. Twenty resistance trained men were randomized and consumed either 1 g of HMB-FA (BetaTor) or placebo (PL) 30 min prior to performing an acute heavy resistance exercise protocol. Blood was obtained before (PRE), immediately after (IP), and 30 min after exercise (30P). Circulating concentrations of testosterone, growth hormone (GH), insulin-like growth factor (IGF-1), and insulin were assayed. Data were analyzed with a repeated measures ANOVA and area under the curve (AUC) was analyzed by the trapezoidal rule.Results. The resistance exercise protocol resulted in significant elevations from PRE in testosteroneP<0.01, GHP<0.01, and insulinP=0.05at IP, with GHP<0.01and insulinP<0.01remaining elevated at 30P. A significant interaction was noted between groups in the plasma GH response at IP, which was significantly higher following HMB-FA compared to PLP<0.01. AUC analysis revealed an elevated GH and IGF-1 response in the HMB-FA group compared to PL.Conclusion. HMB-FA prior to resistance exercise augments the GH response to high volume resistance exercise compared to PL. These findings provide further support for the potential anabolic benefits associated with HMB supplementation.

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Effects of low- and high-volume resistance exercise on postprandial lipaemia Comments by Burns and Stensel

British Journal Of Nutrition ◽

10.1017/s0007114507761755 ◽

2007 ◽

Vol 99 (1) ◽

pp. 211-211 ◽

Cited By ~ 3

Author(s):

Stephen F. Burns ◽

David J. Stensel

Keyword(s):

Resistance Exercise ◽

Area Under The Curve ◽

High Volume ◽

Postprandial Lipaemia ◽

Volume Resistance

Zafeiridis et al.1 recently described the effects of resistance exercise on postprandial TAG concentrations. Zafeiridis and colleagues observed a reduction in 6 h total and incremental TAG area under the curve concentrations after resistance exercise protocols expending approximately 0·76 and 1·40 MJ.

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Overnight responses of the circulating IGF-I system after acute, heavy-resistance exercise

Journal of Applied Physiology ◽

10.1152/jappl.2001.90.4.1319 ◽

2001 ◽

Vol 90 (4) ◽

pp. 1319-1326 ◽

Cited By ~ 61

Author(s):

Bradley C. Nindl ◽

William J. Kraemer ◽

James O. Marx ◽

Paul J. Arciero ◽

Kei Dohi ◽

...

Keyword(s):

Growth Factor ◽

Resistance Exercise ◽

High Volume ◽

Systemic Circulation ◽

Insulin Like Growth Factor ◽

Exercise Protocol ◽

Igf I ◽

Heavy Resistance Exercise ◽

The Impact ◽

Igfbp 3

This study evaluated the individual components of the insulin-like growth factor I (IGF-I) system [i.e., total and free IGF-I, insulin-like growth factor binding protein (IGFBP)-2 and -3, and the acid-labile subunit (ALS)] in 10 young, healthy men (age: 22 ± 1 yr, height: 177 ± 2 cm, weight: 79 ± 3 kg, body fat: 11 ± 1%) overnight for 13 h after two conditions: a resting control (Con) and an acute, heavy-resistance exercise protocol (Ex). The Ex was a high-volume, multiset exercise protocol that alternated between 10- and 5-repetition maximum sets with 90-s rest periods between sets. The Ex was performed from 1500 to 1700; blood was obtained immediately postexercise and sampled throughout the night (every 10 min for the first hour and every hour thereafter) until 0600 the next morning. For the first hour, significant differences ( P ≤ 0.05) were only observed for IGFBP-3 (Ex: 3,801 > Con: 3,531 ng/ml). For the overnight responses, no differences were observed for total or free IGF-I or IGFBP-3, whereas IGFBP-2 increased (Ex: 561 > Con: 500 ng/ml) and ALS decreased (Ex: 35 < Con: 39 μg/ml) after exercise. The results from this study suggest that the impact that resistance exercise exerts on the circulating IGF-I system is not in the alteration of the amount of IGF-I but rather of the manner in which IGF-I is partitioned among its family of binding proteins. Thus acute, heavy-resistance exercise can lead to alterations in the IGF-I system that can be detected in the systemic circulation.

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Differences in muscle oxygenation between young and middle-aged recreationally active men during high-volume resistance exercise

Kinesiology ◽

10.26582/k.51.1.4 ◽

2019 ◽

Vol 51 (1) ◽

pp. 3-11

Author(s):

Yftach Gepner ◽

Joseph A. Gordon ◽

Jay R. Hoffman ◽

Jeffrey R. Stout ◽

David H. Fukuda ◽

...

Keyword(s):

Resistance Exercise ◽

Body Mass ◽

Vastus Lateralis ◽

Body Height ◽

High Volume ◽

Muscle Oxygenation ◽

Exercise Session ◽

Vastus Lateralis Muscle ◽

Middle Aged ◽

Volume Resistance

The aim of this study was to compare muscle oxygenation of the vastus lateralis during a high-volume isokinetic resistance exercise protocol (HVP) between young adult (YA) and middle-aged adult (MA) men. Twenty recreationally trained men were assigned to either the YA (age 21.8±2.0 years, body mass 90.7±11.6 kg, body height 179±4.7 cm) or MA (age 47.0±4.4 years, body mass 96.1±21.6 kg, body height 177±7.7 cm) group. The HVP consisted of eight sets of 10 repetitions of unilateral isokinetic concentric knee extension and eccentric knee flexion at 60°·s-1. Changes in tissue hemoglobin saturation index (TSI), tissue oxygenated hemoglobin concentration (O2Hb), deoxygenated hemoglobin (HHb), and muscle oxidation index (O2Hb-HHb) were measured during the exercise session using the near-infrared spectroscopy (NIRS). Data were analyzed using two-way mix factorial analyses of variance. Prior to exercise, TSI was significantly greater (p=.024) for YA compared to MA. Significant decreases in O2Hb and O2Hb-HHb and increases in HHb were observed during each of the eight sets relative to the rest periods (p<.05) for both groups. The average change during the eight sets of the HVP revealed a significantly higher (p=.036) level of HHb and a lower (p=.029) level of O2Hb-HHb for MA compared to YA. A significant negative correlation was also noted at baseline between O2Hb-HHb index and the cross-sectional area of the vastus lateralis muscle (r=-.45, p=.045). During a high- volume resistance exercise, MA experienced reduced muscle oxygen saturation levels compared to YA. These results may be attributed to reductions in local tissue oxidative capacity and reduced blood delivery occurring during middle-age, and possibly due to group differences in muscle morphology.

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Acute Heavy Resistance Exercise Protocol Induces Significant Physiological Stress Elevating Extracellular Heat Shock Protein

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000562886.89657.79 ◽

2019 ◽

Vol 51 (Supplement) ◽

pp. 799

Author(s):

Jacob Bowie ◽

Adam J. Sterczala ◽

William J. Kraemer ◽

Carl M. Maresh ◽

Brett A. Comstock ◽

...

Keyword(s):

Heat Shock ◽

Heat Shock Protein ◽

Resistance Exercise ◽

Physiological Stress ◽

Exercise Protocol ◽

Heavy Resistance Exercise

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Monocyte Recruitment Following High-intensity And High-volume Resistance Exercise

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000486186.56329.70 ◽

2016 ◽

Vol 48 ◽

pp. 393-394 ◽

Cited By ~ 2

Author(s):

Adam J. Wells ◽

Jay R. Hoffman ◽

Adam R. Jajtner ◽

Alyssa N. Varanoske ◽

David D. Church ◽

...

Keyword(s):

Resistance Exercise ◽

High Intensity ◽

High Volume ◽

Monocyte Recruitment ◽

Volume Resistance

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24-Hour Serum Testosterone Concentrations Following Acute Moderate and High-Volume Resistance Exercise

Medicine & Science in Sports & Exercise ◽

10.1249/00005768-200405001-01139 ◽

2004 ◽

Vol 36 (Supplement) ◽

pp. S238

Author(s):

Joseph A. Alemany ◽

Mark D. Kellogg ◽

Marilyn A. Sharp ◽

Alexander P. Tuckow ◽

Jeffery S. Staab ◽

...

Keyword(s):

Resistance Exercise ◽

Serum Testosterone ◽

High Volume ◽

Volume Resistance

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Carbohydrate Mouth Rinsing Enhances The Performance Of High-Volume Resistance Exercise

Medicine & Science in Sports & Exercise ◽

10.1249/01.mss.0000478859.54932.9c ◽

2015 ◽

Vol 47 ◽

pp. 778

Author(s):

Luciana S. Decimoni ◽

Lívia Almeida ◽

Jeffrey M. Willardson ◽

Alexander J. Koch ◽

Marco Machado

Keyword(s):

Resistance Exercise ◽

High Volume ◽

Volume Resistance ◽

Mouth Rinsing

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Responses of IGF-I to endogenous increases in growth hormone after heavy-resistance exercise

Journal of Applied Physiology ◽

10.1152/jappl.1995.79.4.1310 ◽

1995 ◽

Vol 79 (4) ◽

pp. 1310-1315 ◽

Cited By ~ 78

Author(s):

W. J. Kraemer ◽

B. A. Aguilera ◽

M. Terada ◽

R. U. Newton ◽

J. M. Lynch ◽

...

Keyword(s):

Growth Hormone ◽

Creatine Kinase ◽

Resistance Exercise ◽

Acute Exercise ◽

Recovery Period ◽

Exercise Protocol ◽

Significant Relationships ◽

Igf I ◽

Heavy Resistance Exercise ◽

And Control

The purpose of this study was to examine the effects of a heavy-resistance exercise protocol known to dramatically elevate immunoreactive growth hormone (GH) on circulating insulin-like growth factor I (IGF-I) after the exercise stimulus. Seven men (23.1 +/- 2.4 yr) volunteered to participate in this study. Each subject was asked to perform an eight-station heavy-resistance exercise protocol consisting of 3 sets of 10 repetition maximum resistances with 1-min rest between sets and exercises followed by a recovery day. In addition, a control day followed a nonexercise day to provide baseline data. Pre- and postexercise (0, 15, and 30 min) blood samples were obtained and analyzed for lactate, creatinine kinase, GH, and IGF-I. Postexercise values for lactate and GH were significantly (P < 0.05) elevated above preexercise and resting baseline values. The highest mean GH concentration after the heavy-resistance exercise protocol was 23.8 +/- 11.8 micrograms/l, observed at the immediate postexercise time point. Significant increases in creatine kinase were observed after the exercise protocol and during the recovery day. No significant relationships were observed between creatine kinase and IGF-I concentrations. No significant changes in serum IGF-I concentrations were observed with acute exercise or between the recovery and control days. Thus, these data demonstrate that a high-intensity bout of heavy-resistance exercise that increases circulating GH did not appear to affect IGF-I concentrations over a 24-h recovery period in recreationally strength-trained and healthy young men.

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Oral L-Arginine Before Resistance Exercise Blunts Growth Hormone in Strength Trained Males

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2013-0106 ◽

2014 ◽

Vol 24 (2) ◽

pp. 236-244 ◽

Cited By ~ 8

Author(s):

Scott C. Forbes ◽

Vicki Harber ◽

Gordon J. Bell

Keyword(s):

Growth Hormone ◽

Resistance Exercise ◽

Body Mass ◽

Area Under The Curve ◽

Training Experience ◽

Double Blind ◽

Acute Bout ◽

Plasma Gh ◽

Arginine Concentration ◽

And Training

Acute resistance exercise and L-arginine have both been shown to independently elevate plasma growth hormone (GH) concentrations; however, their combined effect is controversial. The purpose was to investigate the combined effects of resistance exercise and L-arginine supplementation on plasma L-arginine, GH, GH secretagogues, and IGF-1 in strength trained participants. Fourteen strength trained males (age: 25 ± 4 y; body mass: 81.4 ± 9.0 kg; height: 179.4 ± 6.9 cm; and training experience: 6.3 ± 3.4 y) participated in a randomized double-blind crossover design (separated by ~7 days). Subjects reported to the laboratory at 08:00 in a fasted state, consumed L-arginine (ARG; 0.075 g·kg−1 body mass) or a placebo (PLA) before performing an acute bout of resistance exercise (3 sets of 8 exercises, 10 repetitions at ~75% 1RM). Blood samples were collected at rest, before exercise, and at 0, 15, 30, and 60 min of rest-recovery. The ARG condition significantly increased plasma L-arginine concentrations (~120%) while no change was detected in the PLA condition. There were no differences between conditions for GH, GH-releasing hormone, ghrelin, or IGF-1 at any time point. GH-inhibiting hormone was significantly lower in the ARG condition. However, integrated area under the curve for GH was blunted in the ARG condition (L-arginine = 288.4 ± 368.7 vs. placebo = 487.9 ± 482.0 min·ng·mL−1, p < .05). L-arginine ingested before resistance exercise significantly elevated plasma L-arginine concentration but attenuated plasma GH in strength trained individuals despite a lower GHIH. Furthermore our data shows that the GH suppression was not due to a GH or IGF-1 induced autonegative feedback loop.

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