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The Impact of Shiftwork on Skeletal Muscle Health. Nutrients 2017; 9:nu9030248. [PMID: 28282858 PMCID: PMC5372911 DOI: 10.3390/nu9030248] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/26/2017] [Accepted: 03/03/2017] [Indexed: 01/11/2023] Open
Abstract
(1) Background: About one in four workers undertake shift rosters that fall outside the traditional 7 a.m.-6 p.m. scheduling. Shiftwork alters workers' exposure to natural and artificial light, sleep patterns, and feeding patterns. When compared to the rest of the working population, shiftworkers are at a greater risk of developing metabolic impairments over time. One fundamental component of metabolic health is skeletal muscle, the largest organ in the body. However, cause-and-effect relationships between shiftwork and skeletal muscle health have not been established; (2) Methods: A critical review of the literature was completed using online databases and reference lists; (3) Results: We propose a conceptual model drawing relationships between typical shiftwork consequences; altered light exposure, sleep patterns, and food and beverage consumption, and drivers of skeletal muscle health-protein intake, resistance training, and hormone release. At present, there is no study investigating the direct effect of shiftwork on skeletal muscle health. Instead, research findings showing that acute consequences of shiftwork negatively influence skeletal muscle homeostasis support the validity of our model; (4) Conclusion: Further research is required to test the potential relationships identified in our review, particularly in shiftwork populations. Part of this testing could include skeletal muscle specific interventions such as targeted protein intake and/or resistance-training.
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Johnston MJ, Cook CJ, Drake D, Costley L, Johnston JP, Kilduff LP. The Neuromuscular, Biochemical, and Endocrine Responses to a Single-Session Vs. Double-Session Training Day in Elite Athletes. J Strength Cond Res 2016; 30:3098-3106. [PMID: 27028155 DOI: 10.1519/jsc.0000000000001423] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Johnston, MJ, Cook, CJ, Drake, D, Costley, L, Johnston, JP, and Kilduff, LP. The neuromuscular, biochemical, and endocrine responses to a single-session vs. double-session training day in elite athletes. J Strength Cond Res 30(11): 3098-3106, 2016-The aim of this study was to compare the acute neuromuscular, biochemical, and endocrine responses of a training day consisting of a speed session only with performing a speed-and-weights training session on the same day. Fifteen men who were academy-level rugby players completed 2 protocols in a randomized order. The speed-only protocol involved performing 6 maximal effort repetitions of 50-m running sprints with 5 minutes of recovery between each sprint, whereas the speed-and-weights protocol involved the same sprinting session but was followed 2 hours later by a lower-body weights session consisting of 4 sets of 5 backsquats and Romanian deadlift at 85% one repetition maximum. Testosterone, cortisol, creatine kinase, lactate, and perceived muscle soreness were determined immediately before, immediately after, 2 hours after, and 24 hours after both the protocols. Peak power, relative peak power, jump height, and average rate of force development were determined from a countermovement jump (CMJ) at the same time points. After 24-hours, muscle soreness was significantly higher after the speed-and-weights protocol compared with the speed-only protocol (effect size η = 0.253, F = 4.750, p ≤ 0.05). There was no significant difference between any of the CMJ variables at any of the posttraining time points. Likewise, creatine kinase, testosterone, and cortisol were unaffected by the addition of a weight-training session. These data indicate that the addition of a weight-training session 2 hours after a speed session, whereas increasing the perception of fatigue the next day does not result in a difference in endocrine response or in neuromuscular capability.
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Affiliation(s)
- Michael J Johnston
- 1Strength and Conditioning Department, English Institute of Sport, Loughborough University, Loughborough, United Kingdom; 2Applied Sports, Technology, Exercise and Medicine (A-STEM) Research Centre, Swansea University, Swansea, United Kingdom; 3School of Sport, Health and Exercise Science, Bangor University, Bangor, United Kingdom; 4Strength and Conditioning Department, Ulster Rugby, Newforge Lane, Belfast, United Kingdom; 5Strength and Conditioning Department, Ulster Sports Academy, University of Ulster, Jordanstown, United Kingdom; and 6Department of Sport Science, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
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Jones TW, Howatson G, Russell M, French DN. Effects of strength and endurance exercise order on endocrine responses to concurrent training. Eur J Sport Sci 2016; 17:326-334. [DOI: 10.1080/17461391.2016.1236148] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Jones TW, Howatson G, Russell M, French DN. Performance and Endocrine Responses to Differing Ratios of Concurrent Strength and Endurance Training. J Strength Cond Res 2016; 30:693-702. [PMID: 26907840 DOI: 10.1519/jsc.0000000000001135] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The present study examined functional strength and endocrine responses to varying ratios of strength and endurance training in a concurrent training regimen. Thirty resistance trained men completed 6 weeks of 3 d·wk of (a) strength training (ST), (b) concurrent strength and endurance training ratio 3:1 (CT3), (c) concurrent strength and endurance training ratio 1:1 (CT1), or (d) no training (CON). Strength training was conducted using whole-body multijoint exercises, whereas endurance training consisted of treadmill running. Assessments of maximal strength, lower-body power, and endocrine factors were conducted pretraining and after 3 and 6 weeks. After the intervention, ST and CT3 elicited similar increases in lower-body strength; furthermore, ST resulted in greater increases than CT1 and CON (all p ≤ 0.05). All training conditions resulted in similar increases in upper-body strength after training. The ST group observed greater increases in lower-body power than all other conditions (all p ≤ 0.05). After the final training session, CT1 elicited greater increases in cortisol than ST (p = 0.008). When implemented as part of a concurrent training regimen, higher volumes of endurance training result in the inhibition of lower-body strength, whereas low volumes do not. Lower-body power was attenuated by high and low frequencies of endurance training. Higher frequencies of endurance training resulted in increased cortisol responses to training. These data suggest that if strength development is the primary focus of a training intervention, frequency of endurance training should remain low.
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Affiliation(s)
- Thomas W Jones
- 1ASPIRE, Academy for Sports Excellence, Doha, Qatar;2Department of Sport, Exercise, and Rehabilitation, Northumbria University, Newcastle upon Tyne, United Kingdom;3Water Research Group, School of Environmental Sciences and Development, North West University, Potchefstroom, South Africa; and4English Institute of Sport, Sportcity, Manchester, United Kingdom
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Altered diurnal pattern of steroid hormones in relation to various behaviors, external factors and pathologies: A review. Physiol Behav 2016; 164:68-85. [DOI: 10.1016/j.physbeh.2016.05.039] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Revised: 05/20/2016] [Accepted: 05/21/2016] [Indexed: 11/17/2022]
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Burley SD, Whittingham-Dowd J, Allen J, Grosset JF, Onambele-Pearson GL. The Differential Hormonal Milieu of Morning versus Evening May Have an Impact on Muscle Hypertrophic Potential. PLoS One 2016; 11:e0161500. [PMID: 27583459 PMCID: PMC5008805 DOI: 10.1371/journal.pone.0161500] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 08/05/2016] [Indexed: 11/21/2022] Open
Abstract
Substantial gains in muscle strength and hypertrophy are clearly associated with the routine performance of resistance training. What is less evident is the optimal timing of the resistance training stimulus to elicit these significant functional and structural skeletal muscle changes. Therefore, this investigation determined the impact of a single bout of resistance training performed either in the morning or evening upon acute anabolic signalling (insulin-like growth factor-binding protein-3 (IGFBP-3), myogenic index and differentiation) and catabolic processes (cortisol). Twenty-four male participants (age 21.4±1.9yrs, mass 83.7±13.7kg) with no sustained resistance training experience were allocated to a resistance exercise group (REP). Sixteen of the 24 participants were randomly selected to perform an additional non-exercising control group (CP) protocol. REP performed two bouts of resistance exercise (80% 1RM) in the morning (AM: 0800 hrs) and evening (PM: 1800 hrs), with the sessions separated by a minimum of 72 hours. Venous blood was collected immediately prior to, and 5 min after, each resistance exercise and control sessions. Serum cortisol and IGFBP-3 levels, myogenic index, myotube width, were determined at each sampling period. All data are reported as mean ± SEM, statistical significance was set at P≤0.05. As expected a significant reduction in evening cortisol concentration was observed at pre (AM: 98.4±10.5, PM: 49.8±4.4 ng/ml, P<0.001) and post (AM: 98.0±9.0, PM: 52.7±6.0 ng/ml, P<0.001) exercise. Interestingly, individual cortisol differences pre vs post exercise indicate a time-of-day effect (AM difference: -2±2.6%, PM difference: 14.0±6.7%, P = 0.03). A time-of-day related elevation in serum IGFBP-3 (AM: 3274.9 ± 345.2, PM: 3605.1 ± 367.5, p = 0.032) was also evident. Pre exercise myogenic index (AM: 8.0±0.6%, PM: 16.8±1.1%) and myotube width (AM: 48.0±3.0, PM: 71.6±1.9 μm) were significantly elevated (P<0.001) in the evening. Post exercise myogenic index was greater AM (11.5±1.6%) compared with PM (4.6±0.9%). No difference was observed in myotube width (AM: 48.5±1.5, PM: 47.8±1.8 μm) (P>0.05). Timing of resistance training regimen in the evening appears to augment some markers of hypertrophic potential, with elevated IGFBP-3, suppressed cortisol and a superior cellular environment. Further investigation, to further elucidate the time course of peak anabolic signalling in morning vs evening training conditions, are timely.
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Affiliation(s)
- Simon D. Burley
- HEAL Research Centre, Exercise & Sport Science, Manchester Metropolitan University, Crewe Green Road, Crewe, CW1 5DU, United Kingdom
| | - Jayde Whittingham-Dowd
- Faculty of Life Sciences, The University of Manchester, AV Hill Building, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Jeremy Allen
- School of Health, Sport & Rehabilitation Sciences, University of Salford, Salford, Greater Manchester M5 4WT, United Kingdom
| | - Jean-Francois Grosset
- HEAL Research Centre, Exercise & Sport Science, Manchester Metropolitan University, Crewe Green Road, Crewe, CW1 5DU, United Kingdom
- CNRS UMR 7338, Biomécanique et Bioingénierie, Université de Technologie de Compiègne, 60205 Compiègne cedex, France
| | - Gladys L. Onambele-Pearson
- HEAL Research Centre, Exercise & Sport Science, Manchester Metropolitan University, Crewe Green Road, Crewe, CW1 5DU, United Kingdom
- * E-mail:
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Four months of combined and compound morning training improves testosterone/cortisol ratio, adiponectin and insulin resistance in male students. SPORT SCIENCES FOR HEALTH 2016. [DOI: 10.1007/s11332-016-0277-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Klentrou P, Giannopoulou A, McKinlay BJ, Wallace P, Muir C, Falk B, Mack D. Salivary cortisol and testosterone responses to resistance and plyometric exercise in 12- to 14-year-old boys. Appl Physiol Nutr Metab 2016; 41:714-8. [PMID: 27176936 DOI: 10.1139/apnm-2015-0668] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined changes in salivary testosterone and cortisol following resistance and plyometric exercise protocols in active boys. In a crossover experimental design, 26 peri-pubertal (12- to 14-year-old) soccer players performed 2 exercise trials in random order, on separate evenings, 1 week apart. Each trial included a 30 min control session followed by 30 min of either resistance or plyometric exercise. Saliva was collected at baseline, post-control (i.e., pre-exercise), and 5 and 30 min post-exercise. There were no significant differences in the baseline hormone concentrations between trials or between weeks (p > 0.05). A significant effect for time was found for testosterone (p = 0.02, [Formula: see text] = 0.14), which increased from pre-exercise to 5 min post-exercise in both the resistance (27% ± 5%) and plyometric (12% ± 6%) protocols. Cortisol decreased to a similar extent in both trials (p = 0.009, [Formula: see text] = 0.19) from baseline to post-control and then to 5 min post-exercise, following its typical circadian decrease in the evening hours. However, a significant protocol-by-time interaction was observed for cortisol, which increased 30 min after the plyometrics (+31% ± 12%) but continued to decrease following the resistance protocol (-21% ± 5%). Our results suggest that in young male athletes, multiple modes of exercise can lead to a transient anabolic state, thus maximizing the beneficial effects on growth and development, when exercise is performed in the evening hours.
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Affiliation(s)
- Panagiota Klentrou
- a Department of Kinesiology, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Angeliki Giannopoulou
- a Department of Kinesiology, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Brandon J McKinlay
- a Department of Kinesiology, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Phillip Wallace
- a Department of Kinesiology, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Cameron Muir
- b Department of Psychology, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Bareket Falk
- a Department of Kinesiology, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Diane Mack
- a Department of Kinesiology, Faculty of Applied Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
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The effect of session order on the physiological, neuromuscular, and endocrine responses to maximal speed and weight training sessions over a 24-h period. J Sci Med Sport 2016; 20:502-506. [PMID: 27036712 DOI: 10.1016/j.jsams.2016.03.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 02/18/2016] [Accepted: 03/18/2016] [Indexed: 11/21/2022]
Abstract
OBJECTIVES Athletes are often required to undertake multiple training sessions on the same day with these sessions needing to be sequenced correctly to allow the athlete to maximize the responses of each session. We examined the acute effect of strength and speed training sequence on neuromuscular, endocrine, and physiological responses over 24h. DESIGN 15 academy rugby union players completed this randomized crossover study. METHODS Players performed a weight training session followed 2h later by a speed training session (weights speed) and on a separate day reversed the order (speed weights). Countermovement jumps, perceived muscle soreness, and blood samples were collected immediately prior, immediately post, and 24h post-sessions one and two respectively. Jumps were analyzed for power, jump height, rate of force development, and velocity. Blood was analyzed for testosterone, cortisol, lactate and creatine kinase. RESULTS There were no differences between countermovement jump variables at any of the post-training time points (p>0.05). Likewise, creatine kinase, testosterone, cortisol, and muscle soreness were unaffected by session order (p>0.05). However, 10m sprint time was significantly faster (mean±standard deviation; speed weights 1.80±0.11s versus weights speed 1.76±0.08s; p>0.05) when speed was sequenced second. Lactate levels were significantly higher immediately post-speed sessions versus weight training sessions at both time points (p<0.05). CONCLUSIONS The sequencing of strength and speed training does not affect the neuromuscular, endocrine, and physiological recovery over 24h. However, speed may be enhanced when performed as the second session.
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Rosa JPP, Rodrigues DF, Silva A, de Moura Simim MA, Costa VT, Noce F, de Mello MT. 2016 Rio Olympic Games: Can the schedule of events compromise athletes' performance? Chronobiol Int 2016; 33:435-40. [PMID: 27003630 DOI: 10.3109/07420528.2016.1150290] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The organizing committee of the 2016 Rio Olympic Games recently announced that some of the preliminary and final competitions will be held at night. The present article discusses the potential harmful effects of these late-night competitions on sleep, circadian rhythms and athletic performance during the Olympic Games. Specifically, night-time competition could lead to injury and may compromise an athlete's decision-making, attentional, physiological and other processes. Consequently, these impacts could negatively affect the performance of athletes and their teams. Thus, it is suggested that technical commissions take special care when creating strategies to minimize harm to the athletes by considering factors such as light exposure, melatonin intake, sleep hygiene and scheduled naps, and training at local competition time. Furthermore, it is necessary for specialists in chronobiology and sleep to engage with members of the national teams to develop an activity schedule for physical, technical, tactical and psychological preparation that accounts for circadian rhythms, thereby creating the best possible environment for the athletes to achieve their ideal performance.
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Affiliation(s)
- João Paulo P Rosa
- a Escola de Educação Física, Fisioterapia e Terapia Ocupacional (EEFFTO) , Universidade Federal de Minas Gerais , Belo Horizonte , MG , Brazil
| | - Dayane F Rodrigues
- a Escola de Educação Física, Fisioterapia e Terapia Ocupacional (EEFFTO) , Universidade Federal de Minas Gerais , Belo Horizonte , MG , Brazil
| | - Andressa Silva
- a Escola de Educação Física, Fisioterapia e Terapia Ocupacional (EEFFTO) , Universidade Federal de Minas Gerais , Belo Horizonte , MG , Brazil
| | - Mário Antônio de Moura Simim
- a Escola de Educação Física, Fisioterapia e Terapia Ocupacional (EEFFTO) , Universidade Federal de Minas Gerais , Belo Horizonte , MG , Brazil
| | - Varley T Costa
- a Escola de Educação Física, Fisioterapia e Terapia Ocupacional (EEFFTO) , Universidade Federal de Minas Gerais , Belo Horizonte , MG , Brazil
| | - Franco Noce
- a Escola de Educação Física, Fisioterapia e Terapia Ocupacional (EEFFTO) , Universidade Federal de Minas Gerais , Belo Horizonte , MG , Brazil
| | - Marco Túlio de Mello
- a Escola de Educação Física, Fisioterapia e Terapia Ocupacional (EEFFTO) , Universidade Federal de Minas Gerais , Belo Horizonte , MG , Brazil
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Shariat A, Kargarfard M, Danaee M, Bahri Mohd Tamrin S. Intensive resistance exercise and circadian salivary testosterone concentrations among young male recreational lifters. J Strength Cond Res 2016; 29:151-8. [PMID: 25051005 DOI: 10.1519/jsc.0000000000000632] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Strength and morphological adaptations to resistance exercise are mediated in part by anabolic hormones such as testosterone, yet the time course of variability in circadian hormone concentrations is not well characterized. This study, investigated how the circadian rhythm of salivary testosterone is altered by resistance exercise in young men. Twenty healthy young male recreational lifters (age, 18.0 ± 1.3 years) with 2 years of experience in weightlifting were recruited. A randomized controlled trial was conducted, and subjects were randomly assigned to either the resistance exercise group (n = 10), who completed a series of resistance exercise (3 times a week, in the afternoon, 6-7 repetitions, at 85% of 1 repetition maximum for 3 weeks), or a control group (n = 10), who did not exercise during the 3 weeks. Before and after the study, an unstimulated saliva sample (2 ml) was taken every 2 hours for a maximum of 16 hours during each day. A significant decrease was observed in the resistance exercise (44.2%, p = 0.001) and control group (46.1%, p = 0.001) for salivary testosterone at each time point compared with baseline (p = 0.001). There was also no significant difference between the exercise and resting conditions in both groups for salivary testosterone (p > 0.05), except a significantly higher increase by 38.4% vs. -0.02% (p = 0.001), at 1730 hours during exercise sessions in the resistance exercise group compared with the control group. Resistance exercise has no noteworthy effect on circadian secretion of salivary testosterone throughout the 16 waking hours. These results indicate that athletes can undertake resistance exercise in either the morning or afternoon with the knowledge that a similar testosterone response can be expected regardless of the time of day.
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Affiliation(s)
- Ardalan Shariat
- 1Department of Sports Science, Faculty of Educational Studies, University Putra Malaysia, Serdang, Malaysia; 2Department of Environmental and Occupational Health, Faculty of Medicine and Health Sciences, University Putra Malaysia, Serdang, Malaysia; 3Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, University of Isfahan, Isfahan, Iran; and 4Department of Biotechnology, Faculty of Agriculture, Roudehen Branch, Islamic Azad University, Roudehen, Iran
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Henselmans M, Schoenfeld BJ. The effect of inter-set rest intervals on resistance exercise-induced muscle hypertrophy. Sports Med 2015; 44:1635-43. [PMID: 25047853 DOI: 10.1007/s40279-014-0228-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Due to a scarcity of longitudinal trials directly measuring changes in muscle girth, previous recommendations for inter-set rest intervals in resistance training programs designed to stimulate muscular hypertrophy were primarily based on the post-exercise endocrinological response and other mechanisms theoretically related to muscle growth. New research regarding the effects of inter-set rest interval manipulation on resistance training-induced muscular hypertrophy is reviewed here to evaluate current practices and provide directions for future research. Of the studies measuring long-term muscle hypertrophy in groups employing different rest intervals, none have found superior muscle growth in the shorter compared with the longer rest interval group and one study has found the opposite. Rest intervals less than 1 minute can result in acute increases in serum growth hormone levels and these rest intervals also decrease the serum testosterone to cortisol ratio. Long-term adaptations may abate the post-exercise endocrinological response and the relationship between the transient change in hormonal production and chronic muscular hypertrophy is highly contentious and appears to be weak. The relationship between the rest interval-mediated effect on immune system response, muscle damage, metabolic stress, or energy production capacity and muscle hypertrophy is still ambiguous and largely theoretical. In conclusion, the literature does not support the hypothesis that training for muscle hypertrophy requires shorter rest intervals than training for strength development or that predetermined rest intervals are preferable to auto-regulated rest periods in this regard.
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Affiliation(s)
- Menno Henselmans
- Bayesian Bodybuilding, Lingsesdijk 46B, 4207 AE, Gorinchem, The Netherlands,
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Araujo S, Cohen D, Hayes L. Six weeks of core stability training improves landing kinetics among female capoeira athletes: a pilot study. J Hum Kinet 2015; 45:27-37. [PMID: 25964807 PMCID: PMC4415841 DOI: 10.1515/hukin-2015-0004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Core stability training (CST) has increased in popularity among athletes and the general fitness population despite limited evidence CST programmes alone lead to improved athletic performance. In female athletes, neuromuscular training combining balance training and trunk and hip/pelvis dominant CST is suggested to reduce injury risk, and specifically peak vertical ground reaction forces (vGRF) in a drop jump landing task. However, the isolated effect of trunk dominant core stability training on vGRF during landing in female athletes had not been evaluated. Therefore, the objective of this study was to evaluate landing kinetics during a drop jump test following a CST intervention in female capoeira athletes. After giving their informed written consent, sixteen female capoeira athletes (mean ± SD age, stature, and body mass of 27.3 ± 3.7 years, 165.0 ± 4.0 cm, and 59.7 ± 6.3 kg, respectively) volunteered to participate in the training program which consisted of static and dynamic CST sessions, three times per week for six weeks. The repeated measures T-test revealed participants significantly reduced relative vGRF from pre- to post-intervention for the first (3.40 ± 0.78 vs. 2.85 ± 0.52 N·NBW-1, respectively [p<0.05, effect size = 0.60]), and second landing phase (5.09 ± 1.17 vs. 3.02 ± 0.41 N·NBW-1, respectively [p<0.001, effect size = 0.87]). The average loading rate was reduced from pre- to post-intervention during the second landing phase (30.96 ± 18.84 vs. 12.06 ± 9.83 N·NBW·s-1, respectively [p<0.01, effect size = 0.68]). The peak loading rate was reduced from pre- to post-intervention during the first (220.26 ± 111.51 vs. 120.27 ± 64.57 N·NBW·s-1 respectively [p<0.01, effect size = 0.64]), and second (99.52 ± 54.98 vs. 44.71 ± 30.34 N·NBW·s-1 respectively [p<0.01, effect size = 0.70]) landing phase. Body weight, average loading rate during the first landing phase, and jump height were not significantly different between week 0 and week 6 (p=0.528, p=0.261, and p=0.877, respectively). This study provides evidence that trunk dominant core stability training improves landing kinetics without improving jump height, and may reduce lower extremity injury risk in female athletes.
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Affiliation(s)
- Simone Araujo
- School of Human Science, London Metropolitan Universit, London, UK
| | - Daniel Cohen
- Instituto de Investigaciones, Escuela de Medicina, Universidad de Santander, Bucaramanga, Santander, Colombia
| | - Lawrence Hayes
- School of Human Science, London Metropolitan Universit, London, UK. ; Institute of Clinical Exercise and Health Science, University of the West of Scotland
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Baccouch R, Zarrouk N, Chtourou H, Rebai H, Sahli S. Time-of-day effects on postural control and attentional capacities in children. Physiol Behav 2015; 142:146-51. [DOI: 10.1016/j.physbeh.2015.01.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Revised: 10/05/2014] [Accepted: 01/22/2015] [Indexed: 10/24/2022]
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Di Giminiani R, Fabiani L, Baldini G, Cardelli G, Giovannelli A, Tihanyi J. Hormonal and neuromuscular responses to mechanical vibration applied to upper extremity muscles. PLoS One 2014; 9:e111521. [PMID: 25368995 PMCID: PMC4219718 DOI: 10.1371/journal.pone.0111521] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 09/26/2014] [Indexed: 11/19/2022] Open
Abstract
Objective To investigate the acute residual hormonal and neuromuscular responses exhibited following a single session of mechanical vibration applied to the upper extremities among different acceleration loads. Methods Thirty male students were randomly assigned to a high vibration group (HVG), a low vibration group (LVG), or a control group (CG). A randomized double-blind, controlled-parallel study design was employed. The measurements and interventions were performed at the Laboratory of Biomechanics of the University of L'Aquila. The HVG and LVG participants were exposed to a series of 20 trials ×10 s of synchronous whole-body vibration (WBV) with a 10-s pause between each trial and a 4-min pause after the first 10 trials. The CG participants assumed an isometric push-up position without WBV. The outcome measures were growth hormone (GH), testosterone, maximal voluntary isometric contraction during bench-press, maximal voluntary isometric contraction during handgrip, and electromyography root-mean-square (EMGrms) muscle activity (pectoralis major [PM], triceps brachii [TB], anterior deltoid [DE], and flexor carpi radialis [FCR]). Results The GH increased significantly over time only in the HVG (P = 0.003). Additionally, the testosterone levels changed significantly over time in the LVG (P = 0.011) and the HVG (P = 0.001). MVC during bench press decreased significantly in the LVG (P = 0.001) and the HVG (P = 0.002). In the HVG, the EMGrms decreased significantly in the TB (P = 0.006) muscle. In the LVG, the EMGrms decreased significantly in the DE (P = 0.009) and FCR (P = 0.006) muscles. Conclusion Synchronous WBV acutely increased GH and testosterone serum concentrations and decreased the MVC and their respective maximal EMGrms activities, which indicated a possible central fatigue effect. Interestingly, only the GH response was dependent on the acceleration with respect to the subjects' responsiveness.
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Affiliation(s)
- Riccardo Di Giminiani
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila Italy
- * E-mail:
| | - Leila Fabiani
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Giuliano Baldini
- Laboratory of Chemical-Clinical and Microbiological Analysis, Giulianova Hospital, Teramo, Italy
| | - Giovanni Cardelli
- Laboratory of Chemical-Clinical and Microbiological Analysis, Giulianova Hospital, Teramo, Italy
| | - Aldo Giovannelli
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila Italy
| | - Jozsef Tihanyi
- Department of Biomechanics, Faculty of Physical Education and Sport Sciences, Semmelweis University, Budapest, Hungary
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Fernandes AL, Lopes-Silva JP, Bertuzzi R, Casarini DE, Arita DY, Bishop DJ, Lima-Silva AE. Effect of time of day on performance, hormonal and metabolic response during a 1000-M cycling time trial. PLoS One 2014; 9:e109954. [PMID: 25289885 PMCID: PMC4188634 DOI: 10.1371/journal.pone.0109954] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 09/12/2014] [Indexed: 11/30/2022] Open
Abstract
The aim of this study was to determine the effect of time of day on performance, pacing, and hormonal and metabolic responses during a 1000-m cycling time-trial. Nine male, recreational cyclists visited the laboratory four times. During the 1st visit the participants performed an incremental test and during the 2nd visit they performed a 1000-m cycling familiarization trial. On the 3rd and 4th visits, the participants performed a 1000-m TT at either 8 am or 6 pm, in randomized, repeated-measures, crossover design. The time to complete the time trial was lower in the evening than in the morning (88.2±8.7 versus 94.7±10.9 s, respectively, p<0.05), but there was no significant different in pacing. However, oxygen uptake and aerobic mechanical power output at 600 and 1000 m tended to be higher in the evening (p<0.07 and 0.09, respectively). There was also a main effect of time of day for insulin, cortisol, and total and free testosterone concentration, which were all higher in the morning (+60%, +26%, +31% and +22%, respectively, p<0.05). The growth hormone, was twofold higher in the evening (p<0.05). The plasma glucose was ∼11% lower in the morning (p<0.05). Glucagon, norepinephrine, epinephrine and lactate were similar for the morning and evening trials (p>0.05), but the norepinephrine response to the exercise was increased in the morning (+46%, p<0.05), and it was accompanied by a 5-fold increase in the response of glucose. Muscle recruitment, as measured by electromyography, was similar between morning and evening trials (p>0.05). Our findings suggest that performance was improved in the evening, and it was accompanied by an improved hormonal and metabolic milieu.
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Affiliation(s)
- Alan Lins Fernandes
- Sports Science Research Group, Federal University of Alagoas, Maceio, Alagoas, Brazil, and Department of Physical Education and Sports Science, CAV, Federal University of Pernambuco, Vitória de Santo Antão, Pernambuco, Brazil
| | - João Paulo Lopes-Silva
- Sports Science Research Group, Federal University of Alagoas, Maceio, Alagoas, Brazil, and Department of Physical Education and Sports Science, CAV, Federal University of Pernambuco, Vitória de Santo Antão, Pernambuco, Brazil
| | - Rômulo Bertuzzi
- Endurance Performance Research Group, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Dulce Elena Casarini
- Nephrology Division, Department of Medicine, Federal University of Sao Paulo, São Paulo, Brazil
| | - Danielle Yuri Arita
- Nephrology Division, Department of Medicine, Federal University of Sao Paulo, São Paulo, Brazil
| | - David John Bishop
- Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Australia
| | - Adriano Eduardo Lima-Silva
- Sports Science Research Group, Federal University of Alagoas, Maceio, Alagoas, Brazil, and Department of Physical Education and Sports Science, CAV, Federal University of Pernambuco, Vitória de Santo Antão, Pernambuco, Brazil
- * E-mail:
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Bissonnette R, Risch JE, McElwee KJ, Marchessault P, Bolduc C, Nigen S, Maari C. Changes in serum free testosterone, sleep patterns, and 5-alpha-reductase type I activity influence changes in sebum excretion in female subjects. Skin Res Technol 2014; 21:47-53. [PMID: 25163854 DOI: 10.1111/srt.12155] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/08/2014] [Indexed: 11/30/2022]
Abstract
BACKGROUND/PURPOSE Sebum is thought to play an important role in acne vulgaris and sebum excretion rate (SER) is often used as a marker of efficacy in acne studies. This study explored factors that could induce intra-subject variability in SER. METHODS SER was measured twice, 7 days apart, on the forehead of 40 healthy subjects. At each visit, the following parameters were also evaluated: serum androgen levels, 5-alpha-reductase type I gene expression, forehead temperature, sleep habits, diet, facial washing routine, and UV exposure. RESULTS There was a positive correlation between the time subjects fell asleep on Day 0 and the change in SER for the left (P = 0.010; R = 0.402) and right sides (P = 0.002; R = 0.467) of the forehead. There was a significant inverse correlation between SER and 5-alpha-reductase type 1 expression and between free testosterone levels and 5-alpha-reductase type 1 expression. In sub-analyses performed on men and women, these correlations were only significant for women. CONCLUSION Variations in sleep patterns, free testosterone, and 5-alpha-reductase type 1 activity are associated with changes in sebum excretion in women. This could explain some of the inter-subject variability in SER measured between visits in clinical studies.
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Váczi M, Nagy SA, Kőszegi T, Ambrus M, Bogner P, Perlaki G, Orsi G, Tóth K, Hortobágyi T. Mechanical, hormonal, and hypertrophic adaptations to 10 weeks of eccentric and stretch-shortening cycle exercise training in old males. Exp Gerontol 2014; 58:69-77. [PMID: 25064038 DOI: 10.1016/j.exger.2014.07.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 07/13/2014] [Accepted: 07/23/2014] [Indexed: 10/25/2022]
Abstract
The growth promoting effects of eccentric (ECC) contractions are well documented but it is unknown if the rate of stretch per se plays a role in such muscular responses in healthy aging human skeletal muscle. We tested the hypothesis that exercise training of the quadriceps muscle with low rate ECC and high rate ECC contractions in the form of stretch-shortening cycles (SSCs) but at equal total mechanical work would produce rate-specific adaptations in healthy old males age 60-70. Both training programs produced similar improvements in maximal voluntary isometric (6%) and ECC torque (23%) and stretch-shortening cycle function (reduced contraction duration [24%] and enhanced elastic energy storage [12%]) (p<0.05). The rate of torque development increased 30% only after SSC exercise (p<0.05). Resting testosterone and cortisol levels were unchanged but after each program the acute exercise-induced cortisol levels were 12-15% lower (p<0.05). Both programs increased quadriceps size 2.5% (p<0.05). It is concluded that both ECC and SSC exercise training produces favorable adaptations in healthy old males' quadriceps muscle. Although the rate of muscle tension during the SSC vs. ECC contractions was about 4-fold greater, the total mechanical work seems to regulate the hypetrophic, hormonal, and most of the mechanical adaptations. However, SSC exercise was uniquely effective in improving a key deficiency of aging muscle, i.e., its ability to produce force rapidly.
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Affiliation(s)
- Márk Váczi
- Institute of Sport Sciences and Physical Education, University of Pécs, Ifjúság útja 6., 7624 Pécs, Hungary.
| | - Szilvia A Nagy
- Diagnostic Center of Pécs, Rét utca 2., 7623 Pécs, Hungary.
| | - Tamás Kőszegi
- Institute of Laboratory Medicine, University of Pécs, Szigeti út 2., 7624 Pécs, Hungary.
| | - Míra Ambrus
- Institute of Sport Sciences and Physical Education, University of Pécs, Ifjúság útja 6., 7624 Pécs, Hungary.
| | - Péter Bogner
- Diagnostic Center of Pécs, Rét utca 2., 7623 Pécs, Hungary.
| | - Gábor Perlaki
- Diagnostic Center of Pécs, Rét utca 2., 7623 Pécs, Hungary; MTA-PTE Clinical Neuroscience MR Research Group, Rét utca 2., 7623 Pécs, Hungary.
| | - Gergely Orsi
- Diagnostic Center of Pécs, Rét utca 2., 7623 Pécs, Hungary; MTA-PTE Clinical Neuroscience MR Research Group, Rét utca 2., 7623 Pécs, Hungary.
| | - Katalin Tóth
- Department of Radiography, Faculty of Health Sciences, University of Pécs, 7400 Kaposvár, Hungary.
| | - Tibor Hortobágyi
- Center for Human Movement Sciences, University Medical Center Groningen, A. Deusinglaan 1, 9700 AD Groningen, The Netherlands; Faculty of Health and Life Sciences, Northumbria University, Newcastle-upon-Tyne, UK.
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69
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Seo DY, Lee S, Kim N, Ko KS, Rhee BD, Park BJ, Han J. Morning and evening exercise. Integr Med Res 2013; 2:139-144. [PMID: 28664065 PMCID: PMC5481716 DOI: 10.1016/j.imr.2013.10.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 10/04/2013] [Accepted: 10/04/2013] [Indexed: 11/21/2022] Open
Abstract
A growing body of evidence suggests that exercise may contribute to preventing pathological changes, treating multiple chronic diseases, and reducing mortality and morbidity ratios. Scientific evidence moreover shows that exercise plays a key role in improving health-related physical fitness components and hormone function. Regular exercise training is one of the few strategies that has been strictly adapted in healthy individuals and in athletes. However, time-dependent exercise has different outcomes, based on the exercise type, duration, and hormone adaptation. In the present review, we therefore briefly describe the type, duration, and adaptation of exercise performed in the morning and evening. In addition, we discuss the clinical considerations and indications for exercise training.
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Affiliation(s)
- Dae Yun Seo
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - SungRyul Lee
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Nari Kim
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Kyung Soo Ko
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Byoung Doo Rhee
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Byung Joo Park
- Division of Leisure and Sports Science, Dong Seo University, Busan, Korea
| | - Jin Han
- National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
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Qin F, Zhang J, Cao H, Guo W, Chen L, Shen O, Sun J, Yi C, Li J, Wang J, Tong J. Circadian alterations of reproductive functional markers in male rats exposed to 1800 MHz radiofrequency field. Chronobiol Int 2013; 31:123-33. [DOI: 10.3109/07420528.2013.830622] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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71
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Sedliak M, Zeman M, Buzgó G, Cvečka J, Hamar D, Laczo E, Zelko A, Okuliarová M, Raastad T, Nilsen TS, Kyröläinen H, Häkkinen K, Ahtiainen JP, Hulmi JJ. Effects of time of day on resistance exercise-induced anabolic signaling in skeletal muscle. BIOL RHYTHM RES 2013. [DOI: 10.1080/09291016.2012.740314] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Watabe Y, Tomioka M, Watabe A, Aihara M, Shimba S, Inoue H. The clock gene brain and muscle Arnt-like protein-1 (BMAL1) is involved in hair growth. Arch Dermatol Res 2013; 305:755-61. [PMID: 23955654 DOI: 10.1007/s00403-013-1403-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 07/30/2013] [Accepted: 08/08/2013] [Indexed: 10/26/2022]
Abstract
It is known that baldness caused by androgenetic alopecia is involved with androgen and the androgen receptor. Furthermore, it has been reported that testosterone secretion follows a circadian rhythm. Therefore, we hypothesized that a relationship exists between androgen-induced alopecia and biological rhythm. The mammalian circadian rhythm is controlled by several clock genes. Brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein-1 (BMAL1), one of the clock genes, is a transcription factor that plays central roles in the regulation of circadian rhythms. In this study, we investigated the influence of BMAL1 on hair follicle functions and hair growth. Mice deficient in BMAL1 expression exhibited a delay in hair regrowth after shaving. In hair follicles of mouse vibrissa, expression of Bmal1 and other clock genes was found to be rhythmic. Knockdown of BMAL1 in human follicle dermal papilla cells resulted in modulation of expression of several hair growth-related genes. Therefore, we concluded that expression of clock genes in hair follicles is linked to the circadian rhythm and that BMAL1 can regulate hair growth.
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Affiliation(s)
- Yuichi Watabe
- Division of Stem Cell Therapy (Endowed Chair by ANGFA Co.), St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae, Kawasaki, 216-8511, Japan,
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Hayes LD, Grace FM, Sculthorpe N, Herbert P, Kilduff LP, Baker JS. Does Chronic Exercise Attenuate Age-Related Physiological Decline in Males? Res Sports Med 2013; 21:343-54. [DOI: 10.1080/15438627.2013.825799] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Lawrence D. Hayes
- a Institute of Clinical Exercise and Health Science, University of the West of Scotland , Hamilton , United Kingdom
- b School of Human Sciences, London Metropolitan University , London , United Kingdom
| | - Fergal M. Grace
- a Institute of Clinical Exercise and Health Science, University of the West of Scotland , Hamilton , United Kingdom
| | - Nick Sculthorpe
- a Institute of Clinical Exercise and Health Science, University of the West of Scotland , Hamilton , United Kingdom
- c Department of Sport and Exercise Sciences, University of Bedfordshire , Bedford , United Kingdom
| | - Peter Herbert
- d School of Sport, Health and Outdoor Education, Trinity Saint David, University of Wales , Carmarthen , United Kingdom
| | - Liam P. Kilduff
- e Department of Sports Sciences, Swansea University , Swansea , United Kingdom
| | - Julien S. Baker
- a Institute of Clinical Exercise and Health Science, University of the West of Scotland , Hamilton , United Kingdom
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Chtourou H, Hammouda O, Aloui A, Chaabouni K, Makni-Ayedi F, Wahl M, Chaouachi A, Chamari K, Souissi N. The effect of time of day on hormonal responses to resistance exercise. BIOL RHYTHM RES 2013. [DOI: 10.1080/09291016.2013.805909] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Smith AA, Toone R, Peacock O, Drawer S, Stokes KA, Cook CJ. Dihydrotestosterone is elevated following sprint exercise in healthy young men. J Appl Physiol (1985) 2013; 114:1435-40. [DOI: 10.1152/japplphysiol.01419.2012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Dihydrotestosterone (DHT) exerts both functional and signaling effects extending beyond the effects of testosterone in rodent skeletal muscle. As a primer for investigating the role of DHT in human skeletal muscle function, this study aimed to determine whether circulating DHT is acutely elevated in men following a bout of repeat sprint exercise and to establish the importance of training status and sprint performance to this response. Fourteen healthy active young men (V̇o2max61.0 ± 8.1 ml·kg body mass−1·min−1) performed a bout of repeat sprint cycle exercise at a target workload based on an incremental work-rate maximum (10 × 30 s at 150% Wmaxwith 90-s recovery). Venous blood samples were collected preexercise and 5 and 60 min after exercise. Five minutes after exercise, there were significant elevations in total testosterone (TT; P < 0.001), free testosterone (FT; P < 0.001), and DHT ( P = 0.004), which returned to baseline after 1 h. Changes in DHT with exercise (5 min postexercise − preexercise) correlated significantly with changes in TT ( r = 0.870; P < 0.001) and FT ( r = 0.914; P < 0.001). Sprinting cadence correlated with changes in FT ( r = 0.697; P = 0.006), DHT ( r = 0.625; P = 0.017), and TT ( r = 0.603; P = 0.022), and habitual training volume correlated with the change in TT ( r = 0.569, P = 0.034). In conclusion, our data demonstrate that DHT is acutely elevated following sprint cycle exercise and that this response is influenced by cycling cadence. The importance of DHT in the context of exercise training and sports performance remains to be determined.
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Affiliation(s)
- Alan A. Smith
- Sport, Health and Exercise Science, Department for Health, University of Bath
- United Kingdom Sports Council, London, United Kingdom
| | - Rebecca Toone
- Sport, Health and Exercise Science, Department for Health, University of Bath
| | - Oliver Peacock
- Sport, Health and Exercise Science, Department for Health, University of Bath
| | - Scott Drawer
- United Kingdom Sports Council, London, United Kingdom
| | - Keith A. Stokes
- Sport, Health and Exercise Science, Department for Health, University of Bath
| | - Christian J. Cook
- Sport, Health and Exercise Science, Department for Health, University of Bath
- United Kingdom Sports Council, London, United Kingdom
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Hayes LD, Grace FM, Sculthorpe N, Herbert P, Ratcliffe JW, Kilduff LP, Baker JS. The effects of a formal exercise training programme on salivary hormone concentrations and body composition in previously sedentary aging men. SPRINGERPLUS 2013; 2:18. [PMID: 23396630 PMCID: PMC3566381 DOI: 10.1186/2193-1801-2-18] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 01/14/2013] [Indexed: 12/02/2022]
Abstract
Alteration in body composition, physical function, and substrate metabolism occur with advancing age. These changes may be attenuated by exercise. This study examined whether twenty eight, previously sedentary males (62.5 ± 5.3 years of age; body mass of 89.7 ± 16.4 kg) adhering to the ACSM minimum guidelines for aerobic exercise for six weeks would improve exercise capabilities, body composition and salivary hormone profiles. After six weeks of adhering to the guidelines, salivary testosterone and vo2max (absolute and relative) increased (p < 0.05), whilst body fat percentage and body mass decreased (p < 0.05). Peak power output, fat free mass and cortisol values were not significantly different. Interestingly, salivary testosterone correlated inversely with body fat percentage (R2 = .285, p = 0.011). These results suggest that despite previous inactivity, older males can achieve improvements in cardiorespiratory fitness, body composition and anabolism by adhering to simple lifestyle changes.
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Affiliation(s)
- Lawrence D Hayes
- Institute of Clinical Exercise and Health Science, University of the West of Scotland, Hamilton, Scotland ; School of Human Sciences, London Metropolitan University, 166-220 Holloway Road, London, N7 8DB UK
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Abstract
This article focuses on physical performances after training at a specific time of day. To date, although the effect of time of day on aerobic performances appears to be equivocal, during anaerobic exercises, the effect of time of day has been well established with early morning nadirs and peak performances in the late afternoon. These diurnal rhythms can be influenced by several factors such as the regular training at a specific time of day. Indeed, regular training in the morning hours may increase the lower morning performances to the same or even higher level as their normal diurnal peak typically observed in the late afternoon by a greater increase of performance in the evening. However, regular training in the evening hours may increase the morning-evening (i.e., amplitude of the rhythm) difference by a greater increase of performance in the late afternoon. Therefore, adaptations to training are greater at the time of day at which training is regularly performed than at other times. Nevertheless, although modifications in resting hormones concentrations could explain this time-of-day specific adaptations, precise information on the underlying mechanisms is lacking.
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Affiliation(s)
- Hamdi Chtourou
- Research Laboratory Sports Performance Optimization, National Center of Medicine and Science in Sports (CNMSS), Tunis, Tunisia.
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Portaluppi F, Smolensky MH, Haus E, Fabbian F. Relevance of Chronobiology to the Research and Clinical Practice of Neurorehabilitation. Sleep Med Clin 2012. [DOI: 10.1016/j.jsmc.2012.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Maughan RJ, Zerguini Y, Chalabi H, Dvorak J. Achieving optimum sports performance during Ramadan: some practical recommendations. J Sports Sci 2012; 30 Suppl 1:S109-17. [PMID: 22769241 DOI: 10.1080/02640414.2012.696205] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Muslim athletes should fast from sunrise to sunset each day throughout the 30 days of Ramadan. Most athletes will continue to train throughout Ramadan, and they may also be required to compete at this time, but they will also engage in the religious, cultural, and social activities that Ramadan represents. The available evidence indicates that high-level athletes can maintain performance during Ramadan if physical training, food and fluid intake, and sleep are appropriate and well controlled. Individualized monitoring of athletes may help to prevent fatigue and overtraining and to reduce the risk of consequent illness and injury. The timing and intensity of training may require adjustment to optimize the training response, and training close to or after sunset may have advantages, but this will vary between individual and team sports and between environments that are predominantly Muslim and those that are predominantly non-Muslim. Training late in the day allows nutrition interventions after training to promote adaptations to the training stimulus, to promote recovery, and might help to reduce muscle damage. Sleep deficits have a number of adverse effects on well-being and performance, and athletes should ensure adequate sleep throughout Ramadan. In non-Muslim majority environments, especially in team sports, coaches and athletes should be sensitive to the needs of their team-mates who may be fasting. Event organizers should take account of the needs of Muslim athletes when scheduling the dates and timings of sports competitions.
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Affiliation(s)
- Ronald J Maughan
- School of Sport and Exercise Sciences, Loughborough University, Loughborough, UK.
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Le Panse B, Labsy Z, Baillot A, Vibarel-Rebot N, Parage G, Albrings D, Lasne F, Collomp K. Changes in steroid hormones during an international powerlifting competition. Steroids 2012; 77:1339-44. [PMID: 22917632 DOI: 10.1016/j.steroids.2012.07.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 07/12/2012] [Accepted: 07/19/2012] [Indexed: 01/15/2023]
Abstract
The purpose of this study was to assess changes in the steroid hormone levels of elite athletes during an international powerlifting competition. Baseline cortisol, DHEA and testosterone were determined in saliva samples in 19 (8 men, 11 women) junior and sub-junior athletes on the day before competition, and then on the competition day during the official weighing and in the hour after competition. Performance was determined by total output and the Wilks formula. No change in saliva steroid concentrations was observed between samples collected on the day before competition and the weighing samples. There was no gender effect on cortisol concentrations but saliva testosterone levels were always significantly higher in men than in women (p<0.01), as was end-competition DHEA (p<0.05). Cortisol and DHEA were significantly increased in male and female athletes after the competition (respectively, p<0.01 and p<0.05), whereas end-competition testosterone concentrations were only significantly increased in men (p<0.01). Significant relationships were demonstrated between performance and end-competition cortisol levels in women and end-competition testosterone levels in men. These data indicate that workouts during an international powerlifting competition produce a significant increase in adrenal steroid hormones in both genders, with an increase in male gonadal steroid hormone. Further studies are necessary to examine the changes in oestradiol and progesterone in women and their potential impact on performance during international powerlifting competition.
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Acute resistance training affects cell surface markers for apoptosis and migration in CD4+ and CD8+ lymphocytes. Cell Immunol 2012; 279:134-9. [DOI: 10.1016/j.cellimm.2012.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Revised: 10/31/2012] [Accepted: 11/02/2012] [Indexed: 01/01/2023]
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Drust B, Ahmed Q, Roky R. Circadian variation and soccer performance: Implications for training and match-play during Ramadan. J Sports Sci 2012; 30 Suppl 1:S43-52. [DOI: 10.1080/02640414.2012.703784] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Chtourou H, Chaouachi A, Driss T, Dogui M, Behm DG, Chamari K, Souissi N. The effect of training at the same time of day and tapering period on the diurnal variation of short exercise performances. J Strength Cond Res 2012; 26:697-708. [PMID: 21857363 DOI: 10.1519/jsc.0b013e3182281c87] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The purpose of this investigation was to assess the effects of training and tapering at the same time of the day on the diurnal variations of short exercise performances. Thirty-one physically active men underwent 12 weeks of lower-extremity resistance training and 2 weeks of tapering. These subjects were matched and randomly assigned to a morning training group (MTG, training times 0700-0800 hours, n = 10), an evening training group (ETG, training times 1700-1800 hours, n = 11), and a control group (CG, completed all tests but did not train, n = 10). Muscular strength and power testing was conducted before (T0) and after 12 weeks of training (T1) and after 2 weeks of tapering (T2) in the morning (0700-0800 hours) and in the evening (1700-1800 hours). All morning and evening tests were performed in separate sessions (minimum interval = 36 hours) in a randomized design. In T0, the oral temperature and performances during the Wingate, vertical jump (squat jump and countermovement jump), and maximal voluntary contraction tests were higher in the evening than in the morning for all the groups. In T1, these diurnal variations were blunted in the MTG and persisted in the ETG and CG. In T2, the 2 weeks of tapering resulted in further time of day-specific adaptations and increases in short-term maximal performances. However, there was no significant difference in the relative increase between the MTG and the ETG after both training and tapering. From a practical point of view, if the time of competition is known, training and tapering sessions before a major competition must be conducted at the same time of the day at which one's critical performance is programmed. Moreover, if the time of the competition is not known, a tapering phase after resistance training program could be performed at any time of the day with the same benefit.
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Affiliation(s)
- Hamdi Chtourou
- Tunisian Research Laboratory Sports Performance Optimization National Center of Medicine and Science in Sports (CNMSS), Tunis, Tunisia.
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84
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Forbes-Robertson S, Dudley E, Vadgama P, Cook C, Drawer S, Kilduff L. Circadian disruption and remedial interventions: effects and interventions for jet lag for athletic peak performance. Sports Med 2012; 42:185-208. [PMID: 22299812 DOI: 10.2165/11596850-000000000-00000] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Jet lag has potentially serious deleterious effects on performance in athletes following transmeridian travel, where time zones are crossed eastwards or westwards; as such, travel causes specific effects related to desynchronization of the athlete's internal body clock or circadian clock. Athletes are particularly sensitive to the effects of jet lag, as many intrinsic aspects of sporting performance show a circadian rhythm, and optimum competitive results require all aspects of the athlete's mind and body to be working in tandem at their peak efficiency. International competition often requires transmeridian travel, and competition timings cannot be adjusted to suit individual athletes. It is therefore in the interest of the individual athlete and team to understand the effects of jet lag and the potential adaptation strategies that can be adopted. In this review, we describe the underlying genetic and physiological mechanisms controlling the circadian clock and its inherent ability to adapt to external conditions on a daily basis. We then examine the fundamentals of the various adaptation stimuli, such as light, chronobiotics (e.g. melatonin), exercise, and diet and meal timing, with particular emphasis on their suitability as strategies for competing athletes on the international circuit. These stimuli can be artificially manipulated to produce phase shifts in the circadian rhythm to promote adaptation in the optimum direction, but care must be taken to apply them at the correct time and dose, as the effects produced on the circadian rhythm follow a phase-response curve, with pronounced shifts in direction at different times. Light is the strongest realigning stimulus and careful timing of light exposure and avoidance can promote adjustment. Chronobiotics such as melatonin can also be used to realign the circadian clock but, as well as timing and dosage issues, there are also concerns as to its legal status in different countries and with the World Anti-Doping Agency. Experimental data concerning the effects of food intake and exercise timing on jet lag is limited to date in humans, and more research is required before firm guidelines can be stated. All these stimuli can also be used in pre-flight adaptation strategies to promote adjustment in the required direction, and implementation of these is described. In addition, the effects of individual variability at the behavioural and genetic levels are also discussed, along with the current limitations in assessment of these factors, and we then put forward three case studies, as examples of practical applications of these strategies, focusing on adaptations to travel involving competition in the Rugby Sevens World Cup and the 2016 Summer Olympics in Rio de Janeiro, Brazil. Finally, we provide a list of practice points for optimal adaptation of athletes to jet lag.
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Affiliation(s)
- Sarah Forbes-Robertson
- Sport and Exercise Science Portfolio, School of Engineering, Swansea University, Swansea, UK.
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85
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Mora-Rodríguez R, García Pallarés J, López-Samanes Á, Ortega JF, Fernández-Elías VE. Caffeine ingestion reverses the circadian rhythm effects on neuromuscular performance in highly resistance-trained men. PLoS One 2012; 7:e33807. [PMID: 22496767 PMCID: PMC3319538 DOI: 10.1371/journal.pone.0033807] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 02/22/2012] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To investigate whether caffeine ingestion counteracts the morning reduction in neuromuscular performance associated with the circadian rhythm pattern. METHODS Twelve highly resistance-trained men underwent a battery of neuromuscular tests under three different conditions; i) morning (10:00 a.m.) with caffeine ingestion (i.e., 3 mg kg(-1); AM(CAFF) trial); ii) morning (10:00 a.m.) with placebo ingestion (AM(PLAC) trial); and iii) afternoon (18:00 p.m.) with placebo ingestion (PM(PLAC) trial). A randomized, double-blind, crossover, placebo controlled experimental design was used, with all subjects serving as their own controls. The neuromuscular test battery consisted in the measurement of bar displacement velocity during free-weight full-squat (SQ) and bench press (BP) exercises against loads that elicit maximum strength (75% 1RM load) and muscle power adaptations (1 m s(-1) load). Isometric maximum voluntary contraction (MVC(LEG)) and isometric electrically evoked strength of the right knee (EVOK(LEG)) were measured to identify caffeine's action mechanisms. Steroid hormone levels (serum testosterone, cortisol and growth hormone) were evaluated at the beginning of each trial (PRE). In addition, plasma norepinephrine (NE) and epinephrine were measured PRE and at the end of each trial following a standardized intense (85% 1RM) 6 repetitions bout of SQ (POST). RESULTS In the PM(PLAC) trial, dynamic muscle strength and power output were significantly enhanced compared with AM(PLAC) treatment (3.0%-7.5%; p≤0.05). During AM(CAFF) trial, muscle strength and power output increased above AM(PLAC) levels (4.6%-5.7%; p≤0.05) except for BP velocity with 1 m s(-1) load (p = 0.06). During AM(CAFF), EVOK(LEG) and NE (a surrogate of maximal muscle sympathetic nerve activation) were increased above AM(PLAC) trial (14.6% and 96.8% respectively; p≤0.05). CONCLUSIONS These results indicate that caffeine ingestion reverses the morning neuromuscular declines in highly resistance-trained men, raising performance to the levels of the afternoon trial. Our electrical stimulation data, along with the NE values, suggest that caffeine increases neuromuscular performance having a direct effect in the muscle.
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86
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Stanton A. Hormone Replacement in Men. Integr Med (Encinitas) 2012. [DOI: 10.1016/b978-1-4377-1793-8.00034-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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87
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Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training. Eur J Appl Physiol 2011; 112:2693-702. [PMID: 22105707 PMCID: PMC3371329 DOI: 10.1007/s00421-011-2246-z] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2011] [Accepted: 11/09/2011] [Indexed: 12/31/2022]
Abstract
The purpose of this study was to investigate associations between acute exercise-induced hormone responses and adaptations to high intensity resistance training in a large cohort (n = 56) of young men. Acute post-exercise serum growth hormone (GH), free testosterone (fT), insulin-like growth factor (IGF-1) and cortisol responses were determined following an acute intense leg resistance exercise routine at the midpoint of a 12-week resistance exercise training study. Acute hormonal responses were correlated with gains in lean body mass (LBM), muscle fibre cross-sectional area (CSA) and leg press strength. There were no significant correlations between the exercise-induced elevations (area under the curve—AUC) of GH, fT and IGF-1 and gains in LBM or leg press strength. Significant correlations were found for cortisol, usually assumed to be a hormone indicative of catabolic drive, AUC with change in LBM (r = 0.29, P < 0.05) and type II fibre CSA (r = 0.35, P < 0.01) as well as GH AUC and gain in fibre area (type I: r = 0.36, P = 0.006; type II: r = 0.28, P = 0.04, but not lean mass). No correlations with strength were observed. We report that the acute exercise-induced systemic hormonal responses of cortisol and GH are weakly correlated with resistance training-induced changes in fibre CSA and LBM (cortisol only), but not with changes in strength.
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88
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Portaluppi F, Fabbian F, Manfredini F, Manfredini R. Lack of Time-of-Day Differences Is Not Necessarily Indicative of Lack of Circadian Influences. Chronobiol Int 2011; 28:731-3; author reply 733. [DOI: 10.3109/07420528.2011.609628] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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89
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Vicencio JM, Estrada M, Galvis D, Bravo R, Contreras AE, Rotter D, Szabadkai G, Hill JA, Rothermel BA, Jaimovich E, Lavandero S. Anabolic androgenic steroids and intracellular calcium signaling: a mini review on mechanisms and physiological implications. Mini Rev Med Chem 2011; 11:390-8. [PMID: 21443511 DOI: 10.2174/138955711795445880] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 01/21/2011] [Indexed: 02/05/2023]
Abstract
Increasing evidence suggests that nongenomic effects of testosterone and anabolic androgenic steroids (AAS) operate concertedly with genomic effects. Classically, these responses have been viewed as separate and independent processes, primarily because nongenomic responses are faster and appear to be mediated by membrane androgen receptors, whereas long-term genomic effects are mediated through cytosolic androgen receptors regulating transcriptional activity. Numerous studies have demonstrated increases in intracellular Ca2+ in response to AAS. These Ca2+ mediated responses have been seen in a diversity of cell types, including osteoblasts, platelets, skeletal muscle cells, cardiac myocytes and neurons. The versatility of Ca2+ as a second messenger provides these responses with a vast number of pathophysiological implications. In cardiac cells, testosterone elicits voltage-dependent Ca2+ oscillations and IP3R-mediated Ca2+ release from internal stores, leading to activation of MAPK and mTOR signaling that promotes cardiac hypertrophy. In neurons, depending upon concentration, testosterone can provoke either physiological Ca2+ oscillations, essential for synaptic plasticity, or sustained, pathological Ca2+ transients that lead to neuronal apoptosis. We propose therefore, that Ca2+ acts as an important point of crosstalk between nongenomic and genomic AAS signaling, representing a central regulator that bridges these previously thought to be divergent responses.
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Affiliation(s)
- J M Vicencio
- Center for Molecular Studies of the Cell, Faculty of Chemical and Pharmaceutical Sciences/Faculty of Medicine, University of Chile, Santiago, Chile
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90
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Krüger K, Agnischock S, Lechtermann A, Tiwari S, Mishra M, Pilat C, Wagner A, Tweddell C, Gramlich I, Mooren FC. Intensive resistance exercise induces lymphocyte apoptosis via cortisol and glucocorticoid receptor-dependent pathways. J Appl Physiol (1985) 2011; 110:1226-32. [PMID: 21393471 DOI: 10.1152/japplphysiol.01295.2010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Intensive endurance exercise is known to induce lymphocyte apoptosis, which might affect immune function. Less is known about the effects of resistance exercise on apoptosis and its underlying mechanisms. In this study, subjects performed an intensive resistance test (IRT) and a moderate resistance test, and lymphocyte apoptosis, apoptosis-related parameters, and underlying mechanisms were investigated. IRT induced a significant increase of lymphocyte apoptosis 3 h after exercise, which was accompanied by a significant decrease of mitochondrial membrane potential, a reduction of Bcl-2, and an upregulation of the CD95 receptor. Blood lactate, IL-6, C-reactive protein, and cortisol increased significantly 3 h after IRT. A significant correlation was observed between the increase of apoptosis and cortisol levels 3 h after IRT. Incubation of freshly isolated lymphocytes in IRT serum indicated an important role of serum correlates for apoptosis induction. Selective incubation of lymphocytes in concentrations of selected serum parameters corresponding to levels found post in IRT serum demonstrated a major role for cortisol in apoptosis induction. This result was confirmed by attenutation of apoptosis after addition of mifepristone before incubation in IRT serum. In summary, resistance exercise induced lymphocyte apoptosis in an intensity-dependent way. Furthermore, cortisol signaling via glucocorticoid receptors might be an important mechanism for lymphocyte apoptosis after resistance exercise.
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Affiliation(s)
- K Krüger
- Department of Sports Medicine, Institute of Sports Sciences, Justus-Liebig-University Giessen, Giessen, Germany.
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91
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West DWD, Burd NA, Phillips SM. Comment and reply on: Interactions of cortisol, testosterone, and resistance training: influence of circadian rhythms. Chronobiol Int. 2010; 27(4): 675-705. Chronobiol Int 2010; 27:1943-5; author reply 1945-6. [PMID: 20969533 DOI: 10.3109/07420528.2010.515325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Hayes LD, Bickerstaff GF, Baker JS. AUTHORS' REPLY. Chronobiol Int 2010. [DOI: 10.3109/07420528.2010.517335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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