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R J Rose - One of the best experts on this subject based on the ideXlab platform.
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haematological and biochemical responses to training and Overtraining
Equine Veterinary Journal, 2010Co-Authors: Catherine M Tylermcgowan, Lorraine C Golland, D L Evans, David R Hodgson, R J RoseAbstract:We sought a physiological marker of Overtraining in horses, using commonly practised field and laboratory tests to allow early prediction and treatment of the syndrome. Thirteen Standardbred horses were trained as follows: phase 1 (endurance, 7 weeks), phase 2 (high intensity, 9 weeks) and phase 3 (overload, 18 weeks). In phase 3 the horses were divided into 2 groups: overload training (OLT) and control (C). The OLT group exercised at greater intensities, frequencies and durations than the C group. Overtraining occurred after 31 weeks and was defined as a significant decrease in treadmill run time to fatigue (RT) in response to a standardised exercise test (SET). Variables measured included: feed intake, bodyweight (BWT), resting haematology and plasma biochemistry and treadmill SETs to measure RT. The OLT group had a decrease in BWT after week 28 (P < 0.05) without a reduction in feed intake and a reduction in RT during the SET after 31 weeks. Signs persisted after 2 weeks of a reduced training load confirming Overtraining. Haematology and biochemistry failed to detect any markers of Overtraining. Although no physiological markers of Overtraining were identified, empirical observations revealed that the behaviour of horses in the OLT group was different from those in the C group during the period of Overtraining. This study reflects that a model of Overtraining has been developed based on measurement of a reduction in performance; however, there were no consistent changes in haematology or serum biochemical values in association with the decrement in performance capacity.
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effects of prolonged training Overtraining and detraining on skeletal muscle metabolites and enzymes
Equine Veterinary Journal, 2010Co-Authors: C M Mcgowan, Lorraine C Golland, David L Evans, D R Hodgson, R J RoseAbstract:Thirteen Standardbred horses trained intensively for 34 weeks and detrained for 12 weeks to investigate the effects of training, Overtraining and detraining on muscle metabolites, buffering capacity and enzyme activities (CS, HAD and LDH). After a standardised exercise test to fatigue at 10 m/s (approximately 100% VO2max), there was significant depletion of [ATP], [PCr] and muscle [glycogen] and accumulation of muscle and plasma [lactate], [NH3] and elevated muscle temperature. After training, associated with increased run time to fatigue (148%), there was reduced depletion of muscle [glycogen] and increased [NH3] and muscle temperature at fatigue. Training resulted in increased muscle buffering capacity (19%) and activities of CS (29%) and HAD (32%) and reduced glycogen utilisation (1.32 mmol/s in week 1 to 0.58 mmol/s in week 32). Plasma [lactate] at fatigue increased with training as opposed to muscle [lactate] implying enhanced ability to remove lactate from muscle. Overtraining resulted in reduced run time and associated effects in overtrained horses. While muscle [glycogen] prior to exercise was lower in overtrained horses, glycogen utilisation/s was not reduced and it may not, therefore, have caused the reduced run time. Prolonged high intensity training caused primarily aerobic adaptations and poor performance associated with Overtraining may not be due to metabolic disturbances.
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skeletal muscle adaptations to prolonged training Overtraining and detraining in horses
Pflügers Archiv: European Journal of Physiology, 1998Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Thirteen standard-bred horses were trained intensively for 34 weeks and detrained for 6 weeks to study skeletal muscle adaptations to prolonged training, Overtraining and detraining. Training included endurance (phase 1, 7 weeks), high-intensity (phase 2, 9 weeks) and overload training (OLT) (phase 3, 18 weeks). During phase 3, horses were divided into two groups, OLT and control (C), with OLT horses performing greater intensities and durations of exercise than C horses. Overtraining was evident in OLT horses after week 31 and was defined as a significant reduction in treadmill run time in response to a standardised exercise test (P<0.05). Relationships between peripheral (skeletal muscle) and whole body (maximum O2 uptake, V.O2, max, treadmill run time) adaptations to training were determined. Prolonged training resulted in significant adaptations in morphological characteristics of skeletal muscle but the adaptations were limited and largely completed by 16 weeks of training. Fibre area increased in all fibres while the number of capillaries per fibre increased and the diffusional index (area per capillary) decreased. Mitochondrial volume density continued to increase throughout 34 weeks of training and paralleled increases in V.O2,max and treadmill run time. Significant correlations were noted between mitochondrial volume and V.O2,max (R=0.71), run time and V.O2,max (R=0.83) and mitochondrial volume and run time (R=0.57). We conclude that many of adaptive responses of muscle fibre area and capillarity occur in the initial training period but that markers of oxidative capacity of muscle indicate progressive increases in aerobic capacity with increases in training load. The lack of differences between C and OLT groups indicated that there may be an upper limit to the ability of training stimulus to evoke skeletal muscle adaptive responses. There was no effect of Overtraining or detraining on any of the adaptive responses measured.
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changes in maximum oxygen uptake during prolonged training Overtraining and detraining in horses
Journal of Applied Physiology, 1996Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Tyler, Catherine M., Lorraine C. Golland, David L. Evans, David R. Hodgson, and Reuben J. Rose. Changes in maximum oxygen uptake during prolonged training, Overtraining, and detraining in horses. J...
Andrew C Fry - One of the best experts on this subject based on the ideXlab platform.
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changes in resting mitogen activated protein kinases following resistance exercise overreaching and Overtraining
European Journal of Applied Physiology, 2016Co-Authors: Justin X Nicoll, Andrew C Fry, Andrew J Galpin, Adam J Sterczala, Donald B Thomason, Christopher A Moore, Lawrence W Weiss, Loren Z F ChiuAbstract:Many physiological maladaptations persist after overreaching and Overtraining resistance exercise (RE). However, no studies have investigated changes in mitogen-activated protein kinases (MAPK) after Overtraining in humans, despite their critical role regulating exercise-induced muscular adaptations. The purpose of this study was to describe the changes in total and resting phosphorylation status of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH2-terminal kinase (JNK) and p38-MAPK following a period of RE overreaching or Overtraining. Following 2–4 weeks of normal training (low volume/low intensity), two groups of males performed either a high-power overreaching protocol (HPOR n = 6, mean ± SD, age 23 ± 3.4 years, mass 86.5 ± 17.7 kg, height 1.77 ± 0.06 m) or high-intensity Overtraining protocol (HIOT n = 8, age 19.8 ± 1.8 years, mass 76.8 ± 6.7 kg, height 1.8 ± 0.06 m). Resting muscle biopsies were obtained at baseline (BL; end of normal training period) and 24 h after the final session of stressful training (i.e., HPOR or HIOT programs). Total MAPK and ratio of phosphorylated/total (p-MAPK)- ERK1/2, JNK, and p38-MAPK were analyzed via western blotting. 2 × 2 (group × time) ANOVA determined differences in MAPK between BL and post-training protocols. Compared to BL, total-ERK increased after HPOR, but decreased after HIOT (p ≤ 0.05). p-ERK1/2/total-ERK increased after HIOT (p ≤ 0.05). The ratio of p-JNK/total-JNK and p-ERK1/2/total-ERK decreased after HPOR (p ≤ 0.05); however, this result was primarily due to increased total MAPK content. p-p38-MAPK decreased after HPOR (p ≤ 0.05). Total and p-MAPK are differentially expressed after HPOR and HIOT RE. These changes are likely involved in the maladaptation reported in overreaching and Overtraining exercise. This is the first study describing altered MAPK in RE overtrained and overreached humans.
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β2 adrenergic receptor downregulation and performance decrements during high intensity resistance exercise Overtraining
Journal of Applied Physiology, 2006Co-Authors: Andrew C Fry, Lawrence W Weiss, Brian K Schilling, Loren Z F ChiuAbstract:Previous research on Overtraining due to excessive use of maximal resistance exercise loads [100% 1 repetition maximum (1 RM)] indicates that peripheral muscle maladaptation contributes to overtrai...
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Overtraining in sport
1997Co-Authors: Richard B Kreider, Andrew C Fry, Mary Louise OtooleAbstract:"Overtraining in Sport" is the first comprehensive text on the physiological, biomedical, and psychological aspects of Overtraining and overreaching in sport. Thirty-three leading researchers contribute 17 chapters to this multidisciplinary review of recent findings. Since the research is multidisciplinary, information is presented in an easy-to-understand manner and background information is provided for those who may not have a comprehensive understanding of each subject area."Overtraining in Sport" is divided into seven sections: Section I examines the prevalence, physiological responses, and methods of monitoring and preventing Overtraining in endurance athletes. Section II discusses Overtraining in strength/power athletes and their responses to changes in factors such as resistance volume and intensity. Section III considers medical consequences of Overtraining, including cardiovascular and hematological responses, neuroendocrine responses, and musculoskeletal and orthopedic effects. Section IV covers immune system responses to Overtraining and possible interventions to prevent immunosuppression. Section V documents nutritional factors that may play a part in Overtraining. Section VI discusses the psychological aspects of Overtraining and covers potential treatment and prevention methods. Section VII summarizes the current status of Overtraining research and points to future research needs and directions. This valuable reference should be on the bookshelf of anyone with a serious interest in the potential effects of training too often or too intensely.
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resistance exercise Overtraining and overreaching neuroendocrine responses
Sports Medicine, 1997Co-Authors: Andrew C Fry, William J KraemerAbstract:Overtraining is defined as an increase in training volume and/or intensity of exercise resulting in performance decrements. Recovery from this condition often requires many weeks or months. A shorter or less severe variation of Overtraining is referred to as overreaching, which is easily recovered from in just a few days. Many structured training programmes utilise phases of overreaching to provide variety of the training stimulus. Much of the scientific literature on Overtraining is based on aerobic activities, despite the fact that resistance exercise is a large component of many exercise programmes. Chronic resistance exercise can result in differential responses to Overtraining depending on whether either training volume or training intensity is excessive. The neuroendocrine system is a complex physiological entity that can influence many other systems. Neuroendocrine responses to high volume resistance exercise Overtraining appear to be somewhat similar to Overtraining for aerobic activities. On the other hand, excessive resistance training intensity produces a distinctly different neuroendocrine profile. As a result, some of the neuroendocrine characteristics often suggested as markers of Overtraining may not be applicable to some Overtraining scenarios. Further research will permit elucidation of the interactions between the neuroendocrine system and other physiological systems in the aetiology of performance decrements from Overtraining.
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performance decrements with high intensity resistance exercise Overtraining
Medicine and Science in Sports and Exercise, 1994Co-Authors: Andrew C Fry, William J Kraemer, F Van Borselen, James M Lynch, Joseph L Marsit, E P Roy, N T Triplett, H G KnuttgenAbstract:The purpose of this investigation was to study a high-intensity resistance exercise Overtraining protocol resulting in muscular strength decrements. Seventeen weight-trained males were divided into an Overtraining group (OT; N = 11; mean +/- SE, age = 22.0 +/- 0.9 yr,) that exercised on a squat machine daily for 2 wk with 100% of 1 repetition maximum (RM) relative intensity, and a control group (CON; N = 6; age = 23.7 +/- 2.4 yr) that exercised 1 d.wk-1 with low intensity (50% 1 RM). Test batteries were conducted at the beginning (test 1), after 1 wk (test 2), and after 2 wk (test 3) of the study. One RM performance significantly decreased from test 1 to test 3 (P < 0.05) for the OT group (mean = -12.2 +/- 3.8 kg), but not the CON group (mean = -1.1 +/- 0.8 kg). Isokinetic and stimulated isometric muscle force significantly decreased for the OT group compared with the CON group by test 3. The primary site of maladaptation appeared to be in the periphery as indicated by changes in stimulated force, circulating CK activity, and exercise-induced lactate responses. This protocol produced a significant decrease in 1 RM performance, thus providing a model for the study of short-term, high-intensity resistance exercise Overtraining.
Lorraine C Golland - One of the best experts on this subject based on the ideXlab platform.
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haematological and biochemical responses to training and Overtraining
Equine Veterinary Journal, 2010Co-Authors: Catherine M Tylermcgowan, Lorraine C Golland, D L Evans, David R Hodgson, R J RoseAbstract:We sought a physiological marker of Overtraining in horses, using commonly practised field and laboratory tests to allow early prediction and treatment of the syndrome. Thirteen Standardbred horses were trained as follows: phase 1 (endurance, 7 weeks), phase 2 (high intensity, 9 weeks) and phase 3 (overload, 18 weeks). In phase 3 the horses were divided into 2 groups: overload training (OLT) and control (C). The OLT group exercised at greater intensities, frequencies and durations than the C group. Overtraining occurred after 31 weeks and was defined as a significant decrease in treadmill run time to fatigue (RT) in response to a standardised exercise test (SET). Variables measured included: feed intake, bodyweight (BWT), resting haematology and plasma biochemistry and treadmill SETs to measure RT. The OLT group had a decrease in BWT after week 28 (P < 0.05) without a reduction in feed intake and a reduction in RT during the SET after 31 weeks. Signs persisted after 2 weeks of a reduced training load confirming Overtraining. Haematology and biochemistry failed to detect any markers of Overtraining. Although no physiological markers of Overtraining were identified, empirical observations revealed that the behaviour of horses in the OLT group was different from those in the C group during the period of Overtraining. This study reflects that a model of Overtraining has been developed based on measurement of a reduction in performance; however, there were no consistent changes in haematology or serum biochemical values in association with the decrement in performance capacity.
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effects of prolonged training Overtraining and detraining on skeletal muscle metabolites and enzymes
Equine Veterinary Journal, 2010Co-Authors: C M Mcgowan, Lorraine C Golland, David L Evans, D R Hodgson, R J RoseAbstract:Thirteen Standardbred horses trained intensively for 34 weeks and detrained for 12 weeks to investigate the effects of training, Overtraining and detraining on muscle metabolites, buffering capacity and enzyme activities (CS, HAD and LDH). After a standardised exercise test to fatigue at 10 m/s (approximately 100% VO2max), there was significant depletion of [ATP], [PCr] and muscle [glycogen] and accumulation of muscle and plasma [lactate], [NH3] and elevated muscle temperature. After training, associated with increased run time to fatigue (148%), there was reduced depletion of muscle [glycogen] and increased [NH3] and muscle temperature at fatigue. Training resulted in increased muscle buffering capacity (19%) and activities of CS (29%) and HAD (32%) and reduced glycogen utilisation (1.32 mmol/s in week 1 to 0.58 mmol/s in week 32). Plasma [lactate] at fatigue increased with training as opposed to muscle [lactate] implying enhanced ability to remove lactate from muscle. Overtraining resulted in reduced run time and associated effects in overtrained horses. While muscle [glycogen] prior to exercise was lower in overtrained horses, glycogen utilisation/s was not reduced and it may not, therefore, have caused the reduced run time. Prolonged high intensity training caused primarily aerobic adaptations and poor performance associated with Overtraining may not be due to metabolic disturbances.
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skeletal muscle adaptations to prolonged training Overtraining and detraining in horses
Pflügers Archiv: European Journal of Physiology, 1998Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Thirteen standard-bred horses were trained intensively for 34 weeks and detrained for 6 weeks to study skeletal muscle adaptations to prolonged training, Overtraining and detraining. Training included endurance (phase 1, 7 weeks), high-intensity (phase 2, 9 weeks) and overload training (OLT) (phase 3, 18 weeks). During phase 3, horses were divided into two groups, OLT and control (C), with OLT horses performing greater intensities and durations of exercise than C horses. Overtraining was evident in OLT horses after week 31 and was defined as a significant reduction in treadmill run time in response to a standardised exercise test (P<0.05). Relationships between peripheral (skeletal muscle) and whole body (maximum O2 uptake, V.O2, max, treadmill run time) adaptations to training were determined. Prolonged training resulted in significant adaptations in morphological characteristics of skeletal muscle but the adaptations were limited and largely completed by 16 weeks of training. Fibre area increased in all fibres while the number of capillaries per fibre increased and the diffusional index (area per capillary) decreased. Mitochondrial volume density continued to increase throughout 34 weeks of training and paralleled increases in V.O2,max and treadmill run time. Significant correlations were noted between mitochondrial volume and V.O2,max (R=0.71), run time and V.O2,max (R=0.83) and mitochondrial volume and run time (R=0.57). We conclude that many of adaptive responses of muscle fibre area and capillarity occur in the initial training period but that markers of oxidative capacity of muscle indicate progressive increases in aerobic capacity with increases in training load. The lack of differences between C and OLT groups indicated that there may be an upper limit to the ability of training stimulus to evoke skeletal muscle adaptive responses. There was no effect of Overtraining or detraining on any of the adaptive responses measured.
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changes in maximum oxygen uptake during prolonged training Overtraining and detraining in horses
Journal of Applied Physiology, 1996Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Tyler, Catherine M., Lorraine C. Golland, David L. Evans, David R. Hodgson, and Reuben J. Rose. Changes in maximum oxygen uptake during prolonged training, Overtraining, and detraining in horses. J...
D R Hodgson - One of the best experts on this subject based on the ideXlab platform.
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effects of prolonged training Overtraining and detraining on skeletal muscle metabolites and enzymes
Equine Veterinary Journal, 2010Co-Authors: C M Mcgowan, Lorraine C Golland, David L Evans, D R Hodgson, R J RoseAbstract:Thirteen Standardbred horses trained intensively for 34 weeks and detrained for 12 weeks to investigate the effects of training, Overtraining and detraining on muscle metabolites, buffering capacity and enzyme activities (CS, HAD and LDH). After a standardised exercise test to fatigue at 10 m/s (approximately 100% VO2max), there was significant depletion of [ATP], [PCr] and muscle [glycogen] and accumulation of muscle and plasma [lactate], [NH3] and elevated muscle temperature. After training, associated with increased run time to fatigue (148%), there was reduced depletion of muscle [glycogen] and increased [NH3] and muscle temperature at fatigue. Training resulted in increased muscle buffering capacity (19%) and activities of CS (29%) and HAD (32%) and reduced glycogen utilisation (1.32 mmol/s in week 1 to 0.58 mmol/s in week 32). Plasma [lactate] at fatigue increased with training as opposed to muscle [lactate] implying enhanced ability to remove lactate from muscle. Overtraining resulted in reduced run time and associated effects in overtrained horses. While muscle [glycogen] prior to exercise was lower in overtrained horses, glycogen utilisation/s was not reduced and it may not, therefore, have caused the reduced run time. Prolonged high intensity training caused primarily aerobic adaptations and poor performance associated with Overtraining may not be due to metabolic disturbances.
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skeletal muscle adaptations to prolonged training Overtraining and detraining in horses
Pflügers Archiv: European Journal of Physiology, 1998Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Thirteen standard-bred horses were trained intensively for 34 weeks and detrained for 6 weeks to study skeletal muscle adaptations to prolonged training, Overtraining and detraining. Training included endurance (phase 1, 7 weeks), high-intensity (phase 2, 9 weeks) and overload training (OLT) (phase 3, 18 weeks). During phase 3, horses were divided into two groups, OLT and control (C), with OLT horses performing greater intensities and durations of exercise than C horses. Overtraining was evident in OLT horses after week 31 and was defined as a significant reduction in treadmill run time in response to a standardised exercise test (P<0.05). Relationships between peripheral (skeletal muscle) and whole body (maximum O2 uptake, V.O2, max, treadmill run time) adaptations to training were determined. Prolonged training resulted in significant adaptations in morphological characteristics of skeletal muscle but the adaptations were limited and largely completed by 16 weeks of training. Fibre area increased in all fibres while the number of capillaries per fibre increased and the diffusional index (area per capillary) decreased. Mitochondrial volume density continued to increase throughout 34 weeks of training and paralleled increases in V.O2,max and treadmill run time. Significant correlations were noted between mitochondrial volume and V.O2,max (R=0.71), run time and V.O2,max (R=0.83) and mitochondrial volume and run time (R=0.57). We conclude that many of adaptive responses of muscle fibre area and capillarity occur in the initial training period but that markers of oxidative capacity of muscle indicate progressive increases in aerobic capacity with increases in training load. The lack of differences between C and OLT groups indicated that there may be an upper limit to the ability of training stimulus to evoke skeletal muscle adaptive responses. There was no effect of Overtraining or detraining on any of the adaptive responses measured.
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changes in maximum oxygen uptake during prolonged training Overtraining and detraining in horses
Journal of Applied Physiology, 1996Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Tyler, Catherine M., Lorraine C. Golland, David L. Evans, David R. Hodgson, and Reuben J. Rose. Changes in maximum oxygen uptake during prolonged training, Overtraining, and detraining in horses. J...
Catherine M Tyler - One of the best experts on this subject based on the ideXlab platform.
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skeletal muscle adaptations to prolonged training Overtraining and detraining in horses
Pflügers Archiv: European Journal of Physiology, 1998Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Thirteen standard-bred horses were trained intensively for 34 weeks and detrained for 6 weeks to study skeletal muscle adaptations to prolonged training, Overtraining and detraining. Training included endurance (phase 1, 7 weeks), high-intensity (phase 2, 9 weeks) and overload training (OLT) (phase 3, 18 weeks). During phase 3, horses were divided into two groups, OLT and control (C), with OLT horses performing greater intensities and durations of exercise than C horses. Overtraining was evident in OLT horses after week 31 and was defined as a significant reduction in treadmill run time in response to a standardised exercise test (P<0.05). Relationships between peripheral (skeletal muscle) and whole body (maximum O2 uptake, V.O2, max, treadmill run time) adaptations to training were determined. Prolonged training resulted in significant adaptations in morphological characteristics of skeletal muscle but the adaptations were limited and largely completed by 16 weeks of training. Fibre area increased in all fibres while the number of capillaries per fibre increased and the diffusional index (area per capillary) decreased. Mitochondrial volume density continued to increase throughout 34 weeks of training and paralleled increases in V.O2,max and treadmill run time. Significant correlations were noted between mitochondrial volume and V.O2,max (R=0.71), run time and V.O2,max (R=0.83) and mitochondrial volume and run time (R=0.57). We conclude that many of adaptive responses of muscle fibre area and capillarity occur in the initial training period but that markers of oxidative capacity of muscle indicate progressive increases in aerobic capacity with increases in training load. The lack of differences between C and OLT groups indicated that there may be an upper limit to the ability of training stimulus to evoke skeletal muscle adaptive responses. There was no effect of Overtraining or detraining on any of the adaptive responses measured.
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changes in maximum oxygen uptake during prolonged training Overtraining and detraining in horses
Journal of Applied Physiology, 1996Co-Authors: Catherine M Tyler, Lorraine C Golland, D L Evans, D R Hodgson, R J RoseAbstract:Tyler, Catherine M., Lorraine C. Golland, David L. Evans, David R. Hodgson, and Reuben J. Rose. Changes in maximum oxygen uptake during prolonged training, Overtraining, and detraining in horses. J...
