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Long-standing, insulin-treated type 2 diabetes patients with complications respond well to short-term resistance and interval exercise training.
Praet, SF, Jonkers, RA, Schep, G, Stehouwer, CD, Kuipers, H, Keizer, HA, van Loon, LJ
European journal of endocrinology. 2008;(2):163-72
Abstract
OBJECTIVE To determine the feasibility and the benefits of combined resistance and interval exercise training on phenotype characteristics and skeletal muscle function in deconditioned, type 2 diabetes (T2D) patients with polyneuropathy. DESIGN Short-term, single-arm intervention trial. METHODS Eleven male T2D patients (age: 59.1+/-7.5 years; body mass index: 32.2+/-4.0 kg/m2) performed progressive resistance and interval exercise training thrice a week for 10 weeks. Besides primary diabetes outcome measures, muscle strength (MUST), maximal workload capacity (Wmax), whole-body peak oxygen uptake (VO2peak) and muscle oxidative capacity (MUOX), intramyocellular lipid (IMCL) and glycogen (IMCG) storage, and systemic inflammation markers were determined before and after training. Daily exogenous insulin requirements (EIR) and historic individualized EIR were gathered and analysed. RESULTS MUST and Wmax increased with 17% (90% confidence intervals 9-24%) and 14% (6-21) respectively. Furthermore, mean arterial blood pressure declined with 5.5 mmHg (-9.7 to -1.4). EIR dropped with 5.0 IU/d (-11.5 to 1.5) compared with baseline. A decline of respectively -0.7 mmol/l (-2.9 to 1.5) and -147 micromol/l (-296 to 2) in fasting plasma glucose and non-esterified fatty acids concentrations were observed following the intervention, but these were not accompanied by changes in VO2peak, MUOX, IMCL or IMCG, and blood glycolysated haemoglobin, adiponectin, tumor necrosis factor-alpha and/or cholesterol concentrations. CONCLUSION Short-term resistance and interval exercise training is feasible in deconditioned T2D patients with polyneuropathy and accompanied by moderate improvements in muscle function and blood pressure. Such a specific exercise regimen may provide a better framework for future exercise intervention programmes in the treatment of deconditioned T2D patients.
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2.
Influence of creatine supplementation on 800 m wheelchair performance: a pilot study.
Perret, C, Mueller, G, Knecht, H
Spinal cord. 2006;(5):275-9
Abstract
STUDY DESIGN Double-blind, placebo-controlled, randomly assigned, crossover. OBJECTIVE To assess the influence of a short-term oral creatine supplementation on 800 m wheelchair performance. SETTING Swiss Paraplegic Centre, Nottwil, Switzerland. SUBJECTS In total, six (four male, two female subjects) competitive wheelchair athletes participated in the study. Their age was 33.0+/-9.1 years, height 171.5+/-7.7 cm and weight 63.1+/-6.2 kg. Average weekly training volume was 10.0+/-3.7 h. All of them have been engaged in regular training for over 10.5+/-7.2 years. METHODS During the two treatment periods, subjects ingested 4 x 5 g of creatine monohydrate or placebo (maltodextrin) daily during 6 days in a randomised order. A washout period of 4 weeks lay in-between the two supplementation periods. Before and after each treatment period athletes performed an all-out 800 m wheelchair test on a training roller. Time to complete 800 m, rate of perceived exertion (RPE), lactate concentrations and heart rate were measured. Before each test, body weight was determined. RESULTS Times to complete 800 m before and after creatine supplementation (102.8+/-13.9 versus 100.5+/-11.3 s) compared to before and after placebo supplementation (101.6+/-15.6 versus 99.5+/-13.8 s) were not significantly different. Moreover, for all other parameters measured, no significant differences between creatine and placebo supplementation were found. CONCLUSION A short-term oral creatine supplementation compared to placebo seems not to enhance performance over 800 m in trained, spinal cord-injured, wheelchair athletes.
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3.
A comparison of the clinical and cost-effectiveness of 3 intervention strategies for AIDS wasting.
Shevitz, AH, Wilson, IB, McDermott, AY, Spiegelman, D, Skinner, SC, Antonsson, K, Layne, JE, Beaston-Blaakman, A, Shepard, DS, Gorbach, SL
Journal of acquired immune deficiency syndromes (1999). 2005;(4):399-406
Abstract
OBJECTIVE To compare oxandrolone (OX) or strength training with nutrition alone (NA) for AIDS wasting. SUBJECTS Fifty patients with AIDS; 47 completing the study. INTERVENTIONS Randomization to (1) NA with placebo pills, (2) nutrition with 10 mg of OX administered orally twice a day, or (3) nutrition with progressive resistance training (PRT) for 12 weeks. MAIN OUTCOME MEASURES Midthigh cross-sectional muscle area (CSMA), physical functioning (PF), costs, and cost-effectiveness in dollars/quality-adjusted life-years (dollars/QALYs). RESULTS The OX and PRT subjects had increases in CSMA (7.0% +/- 2.5%, P = 0.01; 5.0% +/- 2.0%, P = 0.04, respectively), although these increases did not differ significantly from the NA arm (NA: 1.0% +/- 1.0%; OX vs. NA: P = 0.09; PRT vs. NA: P = 0.26). Only PRT caused significant improvements in PF (mean +/- SE: 10.4 +/- 3.8 points on a 100-point scale) and 7 measures of strength (P values: 0.04 to <0.001). There were no overall differences between groups in PF change. Among patients with impaired baseline PF, however, OX was significantly less effective than NA and PRT was significantly better than NA. All treatments led to increases in protein intake and performance; NA and PRT also increased caloric intake. The institutional costs per subject in this trial were 983 dollars for NA, 3772 dollars for OX, and 3189 dollars for PRT. At a community-based level of intensity, the institutional costs per QALY were 45,000 dollars (range: 42,000 dollars-64,000 dollars) for NA, 147,000 dollars (range: 147,000 dollars-163,000 dollars) for OX, and 31,000 dollars (range: 21,000 dollars-44,000 dollars) for PRT. CONCLUSIONS OX and PRT induce similar improvements in body composition, but PRT improves quality of life more than nutrition or OX, particularly among patients with impaired PF. PRT was the most cost-effective intervention, and OX was the least cost-effective intervention.
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Does nutritional supplementation influence adaptability of muscle to resistance training in men aged 48 to 72 years.
Carter, JM, Bemben, DA, Knehans, AW, Bemben, MG, Witten, MS
Journal of geriatric physical therapy (2001). 2005;(2):40-7
Abstract
BACKGROUND AND PURPOSE Isotonic strength training can result in neuromuscular improvements evidenced in other forms of muscular effort, ie, isokinetic or isometric, especially in young subjects; however, it is unclear if older muscle maintains this same adaptive ability. Additionally, it is not known if the benefits of resistance training can be augmented by creatine and protein supplementation in older men. Therefore, the purpose of this study was to assess changes in isokinetic parameters at varying speeds in men aged 48 to 72 years (mean=57+/-2.1) following 16 weeks of isotonic resistance training and creatine and/or protein supplementation. METHODS Forty-two male subjects were randomly assigned to 1 of 4 training groups: (1) resistance training placebo (n=10), (2) resistance trained creatine supplemented (n=10), (3) resistance trained protein supplemented (n=11), and (4) resistance trained creatine and protein supplemented (n=11). The program consisted of progressive overload resistance training (3 d/wk) and supplement consumption following the workout. RESULTS There were significant time effects (P>.05) for peak torque (PT), time to PT, and average power for both the knee extensors and flexors at all velocities. However, no significant group or group by time interactions were noted, indicating that the supplementation protocols had no added benefits. CONCLUSIONS Men aged 48 to 72 years maintained their ability to improve isokinetic muscle function following isotonic training, however, supplementation did not enhance muscle adaptability.
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Reliability of the Lode Excalibur Sport Ergometer and applicability to Computrainer electromagnetically braked cycling training device.
Earnest, CP, Wharton, RP, Church, TS, Lucia, A
Journal of strength and conditioning research. 2005;(2):344-8
Abstract
New technology allows cyclists to train via power output (PO) in addition to heart rate (HR). For those athletes undertaking seasonal laboratory testing (e.g., Vo(2), lactate threshold), it is imperative that athletes be able to directly apply this information to their training device. We examined the reliability of a standardized laboratory ergometer (Lode Excalibur Sport) and its applicability to an electromagnetically braked ergometer (Computrainer) in 2 phases. Phase I (n = 12) examined the reliability of the Lode. Phase II (n = 14) compared the Lode to the Computrainer using a randomized, counterbalance assignment. Following warm-up, each trial started at 100 W, progressing 50 W every 3 minutes to exhaustion. Outcomes were time-to-exhaustion (TTE), peak PO (W) (PO(peak)), peak HR (HR(peak)), and ventilatory (VT) and respiratory compensation (RCP) thresholds. We used a repeated measures analysis of variance (ANOVA), Tukey post hoc analysis, regression analysis, Bland-Altman plots, and coefficient of variation (CV) analysis for each variable. During phase I, we found no significant difference for any variable, minimal dispersion of Vo(2) during Bland-Altman analysis, and a low CV at each test stage (≤ 5%). During phase II, significant differences and higher CV for most parameters (all data; p < 0.001) were observed for Lode versus Computrainer: TTE (21 minutes, 12 seconds +/- 3 minutes, 12 seconds vs. 19 minutes, 9 seconds +/- 2 minutes, 36 seconds; CV = 16%), PO(peak) (335 +/- 57.8 W vs. 295 +/- 47.1 W, CV = 17%), as well as PO at VT (CV = 51%) and RCP (CV = 24%; p < 0.01). We conclude that coaches and cyclists may need to use some caution when directly transferring results obtained from laboratory testing to the Computrainer training device.
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The effects of creatine supplementation on muscular performance and body composition responses to short-term resistance training overreaching.
Volek, JS, Ratamess, NA, Rubin, MR, Gómez, AL, French, DN, McGuigan, MM, Scheett, TP, Sharman, MJ, Häkkinen, K, Kraemer, WJ
European journal of applied physiology. 2004;(5-6):628-37
Abstract
To determine the effects of creatine supplementation during short-term resistance training overreaching on performance, body composition, and resting hormone concentrations, 17 men were randomly assigned to supplement with 0.3 g/kg per day of creatine monohydrate (CrM: n=9) or placebo (P: n=8) while performing resistance exercise (5 days/week for 4 weeks) followed by a 2-week taper phase. Maximal squat and bench press and explosive power in the bench press were reduced during the initial weeks of training in P but not CrM. Explosive power in the bench press, body mass, and lean body mass (LBM) in the legs were augmented to a greater extent in CrM ( P
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Musculoskeletal adaptations to 16 weeks of eccentric progressive resistance training in young women.
Schroeder, ET, Hawkins, SA, Jaque, SV
Journal of strength and conditioning research. 2004;(2):227-35
Abstract
We investigated the musculoskeletal adaptations and efficacy of a whole-body eccentric progressive resistance-training (PRT) protocol in young women. Subjects (n = 37; mean age, 24.3) were randomly assigned to one of 3 groups: high-intensity eccentric PRT (HRT), low-intensity eccentric PRT (LRT), or control. Subjects performed 3 sets of 6 repetitions at 125% intensity or 3 sets of 10 repetitions at 75% intensity in the HRT and LRT groups, respectively, 2 times per week for 16 weeks. Strength was determined by the concentric 1-repetition maximum (1RM) standard. Bone mass and body composition were measured by dual-energy x-ray absorptiometry (DXA). Blood and urine samples were obtained for deoxypyridinoline, osteocalcin, creatine kinase, and creatinine. Data were analyzed by repeated-measures analysis of variance with post hoc comparisons. Strength increased 20-40% in both training groups. Lean body mass increased in the LRT (0.7 +/- 0.6 kg) and HRT (0.9 +/- 0.9 kg) groups. Bone mineral content increased (0.855 +/- 0.958 g) in the LRT group only. Deoxypyridinoline decreased and osteocalcin increased in the HRT and LRT groups, respectively. These findings suggest that submaximal eccentric training is optimal for musculoskeletal adaptations and that the intensity of eccentric training influences the early patterns of bone adaptation.
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8.
Muscle metabolism during sprint exercise in man: influence of sprint training.
Barnett, C, Carey, M, Proietto, J, Cerin, E, Febbraio, MA, Jenkins, D
Journal of science and medicine in sport. 2004;(3):314-22
Abstract
In order to examine the influence of sprint training on metabolism and exercise performance during sprint exercise, 16 recreationally-active, untrained, men (VO2peak= 3.8+/-0.1 l.min(-1)) were randomly assigned to either a training (n= 8) or control group (n= 8). Each subject performed a 30-sec cycle sprint and a test to measure VO2peak before and after eight weeks of sprint training. The training group completed a series of sprints three times per week which progressed from three 30-sec cycle sprints in weeks 1 and 2, to six 30-sec sprints in weeks 7 and 8. Three mins of passive recovery separated each sprint throughout the training period. Muscle samples were obtained at rest and immediately following the pre- and post-training sprints and analysed for high energy phosphagens, glycogen and lactate; the activities of both phosphofructokinase (PFK) and citrate synthase (CS) were also measured and muscle fibre types were quantified. Training resulted in a 7.1% increase in mean power output (p<0.05), an 8% increase in VO2peak (p< 0.001), a 42% increase (p< 0.01) in CS activity and a 17% increase (p< 0.05) in resting intramuscular glycogen content. In contrast, neither PFK activity nor fibre type distribution changed with training. An increase (p< 0.05) in mean power output and attenuated (p< 0.01) ATP degradation were observed during sprint exercise following training. Glycogen degradation during sprint exercise was unaffected by sprint training. These data demonstrate that sprint training may have enhanced muscle oxidative but not glycolytic capacity.
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9.
Influence of surface on muscle damage and soreness induced by consecutive drop jumps.
Miyama, M, Nosaka, K
Journal of strength and conditioning research. 2004;(2):206-11
Abstract
This study compared the magnitude of muscle damage induced when consecutive drop jumps (DJs) were performed on sand vs. firm (wood) surfaces from a height of 0.6 m. Eight subjects performed DJs on a sand surface at a depth of 0.2 m (S condition), and 8 other subjects performed DJs on a wood surface (F condition). Each set consisted of 20 DJs with an interval of 10 seconds between jumps. Subjects performed 5 sets of DJs with 2 minutes between sets. Maximal isometric force, muscle soreness, and plasma creatine kinase (CK) activity were measured immediately before and immediately after the DJ exercise as well as 1, 24, 48, 72, and 96 hours after the DJ exercise. All measures changed significantly (p < 0.05) after exercise for both conditions; however, significantly (p < 0.05) smaller changes in these measures were evident for the S condition than for the F condition. These results show that DJs on a sand surface induce less muscle damage than on a firm surface. Training on sand may improve aerobic capacity or strength with a low risk of muscle damage.
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10.
Effect of FIO2 on oxidative stress during interval training at moderate altitude.
Wilber, RL, Holm, PL, Morris, DM, Dallam, GM, Subudhi, AW, Murray, DM, Callan, SD
Medicine and science in sports and exercise. 2004;(11):1888-94
Abstract
PURPOSE To evaluate the effect of different fractions of inspired oxygen (FIO2) on oxidative stress during a high-intensity interval workout in trained endurance athletes residing at altitude. METHODS Subjects (N = 19) were trained male cyclists who were residents of moderate altitude (1800-1900 m). Testing was conducted at 1860 m (PB 610-612 torr, PIO2 approximately 128 torr). Subjects performed three randomized, single-blind trials consisting of a standardized interval workout (6 x 100 kJ) while inspiring a medical-grade gas with FIO2 0.21 (PIO2 approximately 128 torr), FIO2 0.26 (PIO2 approximately 159 torr), and FIO2 0.60 (PIO2 approximately 366 torr). Serum lipid hydroperoxides (LOOH) and whole-blood reduced glutathione (GSH) were measured 60 min preexercise and immediately postexercise, and analyzed using standard colorimetric assays. Urinary malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OHdG) were measured 24 h preexercise and 24 h postexercise, and analyzed via HPLC and ELISA, respectively. RESULTS Compared with the control trial (FIO2 0.21), total time (min:s) for the 100-kJ work interval was faster (5% in FIO2 0.26; 8% in FIO2 0.60 (P < 0.05)) and power output (W) was higher (5% in FIO2 0.26, 8% in FIO2 0.60 (P < 0.05)) in the supplemental oxygen trials. There was a significant pre- versus postexercise main effect (P < 0.05) for LOOH and GSH; however, there were no significant differences in LOOH or GSH between the FIO2 trials. MDA and 8-OHdG were unaffected by either the interval training session or FIO2. CONCLUSION Supplemental oxygen used in conjunction with high-intensity interval training at altitude ("live high + train low via supplemental O2" (LH + TLO2)) results in a significant improvement in exercise performance without inducing additional free radical oxidative stress as reflected in hematological and urinary biomarkers.