SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Strength training with isometric contractions produces large but highly angle-specific adaptations. To contrast the contractile mode of isometric versus dynamic training, but diminish the strong angle specificity effect, we compared the strength gains produced by isometric training at four joint angles with conventional dynamic training. Thirty-three recreationally active healthy males aged 18 - 30 years completed 9 weeks of strength training of the quadriceps muscle group three times per week. An intra-individual design was adopted: one leg performed purely isometric training at each of four joint angles (isometrically trained leg); the other leg performed conventional dynamic training, lifting and lowering (dynamically trained leg). Both legs trained at similar relative loads for the same duration. The quadriceps strength of each leg was measured isometrically (at four angles) and isokinetically (at three velocities) pre and post training. After 9 weeks of training, the increase in isokinetic strength was similar in both legs (pooled data from three velocities: dynamically trained leg, 10.7%; isometrically trained leg, 10.5%). Isometric strength increases were significantly greater for the isometrically trained leg (pooled data from four angles: dynamically trained leg, 13.1%; isometrically trained leg, 18.0%). This may have been due to the greater absolute torque involved with isometric training or a residual angle specificity effect despite the isometric training being divided over four angles.
To investigate the effects of replacing a portion of endurance training by strength training on exercise performance, 14 competitive cyclists were divided into an experimental (E; n = 6) and a control (C; n = 8) group. Both groups received a training program of 9 weeks. The total training volume for both groups was the same [E: 8.8 (1.1) h/week; C: 8.9 (1.7) h/week], but 37% of training for E consisted of explosive-type strength training, whilst C received endurance training only. Simulated time trial performance (TT), short-term performance (STP), maximal workload (Wmax) and gross (GE) and delta efficiency (DE) were measured before, after 4 weeks and at the end of the training program (9 weeks). No significant group-by-training effects for the markers of endurance performance (TT and Wmax) were found after 9 weeks, although after 4 weeks, these markers had only increased (P < 0.05) in E. STP decreased (P < 0.05) in C, whereas no changes were observed in E. For DE, a significant group-by-training interaction (P < 0.05) was found, and for GE the group-by-training interaction was not significant. It is concluded that replacing a portion of endurance training by explosive strength training prevents a decrease in STP without compromising gains in endurance performance of trained cyclists.
While the physiological adaptations that occur following endurance training in previously sedentary and recreationally active individuals are relatively well understood, the adaptations to training in already highly trained endurance athletes remain unclear. While significant improvements in endurance performance and corresponding physiological markers are evident following submaximal endurance training in sedentary and recreationally active groups, an additional increase in submaximal training (i.e. volume) in highly trained individuals does not appear to further enhance either endurance performance or associated physiological variables [e.g. peak oxygen uptake (VO2peak), oxidative enzyme activity]. It seems that, for athletes who are already trained, improvements in endurance performance can be achieved only through high-intensity interval training (HIT). The limited research which has examined changes in muscle enzyme activity in highly trained athletes, following HIT, has revealed no change in oxidative or glycolytic enzyme activity, despite significant improvements in endurance performance (p < 0.05). Instead, an increase in skeletal muscle buffering capacity may be one mechanism responsible for an improvement in endurance performance. Changes in plasma volume, stroke volume, as well as muscle cation pumps, myoglobin, capillary density and fibre type characteristics have yet to be investigated in response to HIT with the highly trained athlete. Information relating to HIT programme optimisation in endurance athletes is also very sparse. Preliminary work using the velocity at which VO2max is achieved (V(max)) as the interval intensity, and fractions (50 to 75%) of the time to exhaustion at V(max) (T(max)) as the interval duration has been successful in eliciting improvements in performance in long-distance runners. However, V(max) and T(max) have not been used with cyclists. Instead, HIT programme optimisation research in cyclists has revealed that repeated supramaximal sprinting may be equally effective as more traditional HIT programmes for eliciting improvements in endurance performance. Further examination of the biochemical and physiological adaptations which accompany different HIT programmes, as well as investigation into the optimal HIT programme for eliciting performance enhancements in highly trained athletes is required.
This study examined the effects of arm training on retention of training effects produced by leg training. Thirteen adult male subjects leg trained on bicycle ergometers for 8 weeks. During the subsequent 4 week control period group AT (N = 4) arm trained by cranking an ergometer, group DT (N = 4) discontinued training and group LT (N = 5) continued leg training. Metabolic response to maximal and submaximal (80% initial Vo2max) leg work was observed before (Test I) and after (Test II) the 8 week leg training program and at the conclusion of the control period (Test III). With the initial 8 weeks of leg training Vo2max and maximal Ve increased while Vo2, HR, Ve and blood lactate decreased during submaximal work (p less than .05). R was decreased during both maximal and submaximal work (p less than .05). Analysis of covariance of the Test III means (Test II as covariate) yielded significant (p less than .05)F-ratios for Vo2max and R at Vo2max. Post hoc testing indicated that Vo2max was greater in LT than in AT or DT but that there was no difference between AT and DT. R at Vo2max was greater in DT than in LT or AT. These data suggest that arm training does not significantly affect the deterioration in metabolic response to leg work which occurs with cessation of leg training.
A study of 1 year was performed on nine elite endurance-trained athletes (swimmers) and on eight elite strength-trained athletes (weightlifters) in order to examine the effects of training on the endocrine responses and on physical performance capacity. The measurements for the determination of serum hormone concentrations were performed at about 4-month intervals during the course of the year. The primary findings demonstrated that during the first and most intensive training period of the year in preparing for the primary competitions similar but statistically insignificant changes were observed in the concentrations of serum testosterone, free testosterone and cortisol in both the endurance-trained and strength-trained groups. After that period the changes in hormonal response over the year were infrequent and minor. A significant (p less than 0.01) decrease occurred in the strength-trained group in serum-free testosterone during the second period, which was characterized by the highest overall amount of training. Over the entire year the concentrations of serum hormones remained statistically unaltered in both groups. Slight but statistically insignificant increases of 1.2% +/- 0.8% and 2.1% +/- 5.1% were observed in the competitive performances over the year in the endurance-trained and strength-trained groups, respectively. The present findings in the two groups of elite athletes, who differed greatly with regard to the type of physiological loading, demonstrated that the overall hormonal responses both during the most intensive and during prolonged training periods were rather similar and the infrequent small changes remained well within the normal physiological range.(ABSTRACT TRUNCATED AT 250 WORDS)
The main aim of this study was to compare the effectiveness of a self-training program in inductive reasoning run for elderly with low levels of education. Two different training settings were considered, i.e. tutor-guided training and self-training, to ascertain whether results obtained in both settings would be similar. A total of 25 subjects took part in this study (average age = 68.266, range = 60-85 years), all volunteers and residents of the city of Granada. A quasi-experimental design was used with random assignment to either training setting. The design was applied in four stages: pre-test, cognitive training (tutor-guided vs. self-trained inductive reasoning), post-test immediately after training and follow-up at 3 months. Results show considerable gains in inductive reasoning training both in tutor-guided and self-trained groups.
The purpose of the study was to compare changes in running economy, foot impact shock, run performance, and resting heart rate and blood pressure elicited by increases in training volume via run training (RT) and cross training (CT). After 30 d of normal training (NT), male runners (N = 11) completed two 10 d periods of increased training each preceded by 14 d of reduced training (80% NT). Subjects ran 10 consecutive days in the afternoon (100% of NT) and performed 8 additional workouts in the morning (100% of NT). The morning sessions were performed on a cycle ergometer (CT) or a treadmill (RT). Running economy, foot impact shock and lactate were assessed during submaximal running (3.9 +/- 0.06 m.sec-1) at D0 and D11. Following the submaximal run, subjects completed a simulated 5 km race on a treadmill. VO2 during the running economy test was significantly higher at D11 of CT (52.5 +/- 1.5) compared to RT (51.1 +/- 1.4 ml.kg-1.min-1). RER, carbohydrate oxidation, and lactate were significantly lower; whereas, foot impact shock was significantly higher following both training modes. No significant changes in run performance, resting heart rate and blood pressure occurred during the study. In summary, 10 d of increased training resulted in a reduced running economy for CT, and a lower carbohydrate oxidation and an increase in foot impact shock for both training modes.
UNLABELLED: 302 male myocardial infarction patients were divided into 4 groups according to their symptom-limited physical working capacity and examined during bicycle ergometer training. Lactic acid and heart rate during training were measured. RESULTS: Arterial lactic acid and training heart rate decreased proportionally with the reduction of the maximal symptom-limited working capacity. Arterial lactic acid levels in 4 training groups of 100, 75, 50 and 25 watts were 2.23 (2.56) mmol/l, 1.87 (2.32) mmol/l, 1.58 (1.73) mmol/l and 1.20 (1.11) mmol/l, respectively, p less than 0.001 (in bracket = with beta blocker). Decrease in arterial lactic acid levels according to the reduction of working capacity corresponded to a decrease of training heart rate. In patients with beta blocker therapy results were less pronounced. Intensity of training corresponded to about 80% of VO2 measured as maximal symptom-limited physical working capacity. Training heart rate corresponded to about 85% of maximal heart rate as measured at symptom-limited physical working capacity. The so-called fixed anaerobic threshold of 4 mmol/l lactic acid was not reached by patients with myocardial infarction up to a training intensity of 100 watts (approximately 1.3 watts/kg). From this study it can be concluded that fixed anaerobic threshold and lactic acid are of secondary importance in determining the intensity of endurance training in patients with myocardial infarction.
The "lanes" concept of training was integrated into a medical site support mission of the 804th Medical Brigade, U.S. Army Reserve, during Annual Training, 1993 at Fort Drum, New York. This training, termed Hospital Integrated Lanes Training (HILT), included STX, FTX, patient play, and full use of Deployable Medical Systems equipment. The medical care of over 33,000 personnel participating in tactical annual training exercises was not interrupted during any concurrent phase of lanes training. Brigade operations planners developed an array of medical exercises that involved both moulaged and paper patient play. These exercises began prior to hospital set-up and continued for 24 hours a day throughout the tactical exercise. Injuries likely to be encountered during combat operations were inserted into the play singly and under a mass-casualty scenario. The standard of care for all injuries was determined with the Army Medical Department Center and School guidance. Prior coordination of brigade medical assets with external air and ground ambulance organizations broadened the scope of the training and facilitated effective use of command and control, communications, and equipment over a wide geographic area. Medical records were collected and evaluated at the conclusion of all exercises. After-action reviews were conducted by all medical units to assist in the planning of future HILT exercises. The HILT concept is a valuable tool for the complex training requirements of field medical units organized under medical Force 2000. The concept of integrated lanes training allows for the development and continuous improvement of individual and sectional skills for medical personnel and should be applied within all echelons of care.
The purpose of this study was to determine the effects of increased training via cross-training (run + cycle) and run training on circulating leukocyte subsets. Male runners (N = 11) participated in two randomly assigned increased training (IT) periods after 30 d of normal training (NT). Each IT began after a 14 d period of reduced training (80% of NT) followed by 10 d of IT (200% of NT). During IT, the subjects ran in the afternoon for 10 d (100% NT) and performed 8 additional training sessions in the morning (100% NT) on a treadmill (ITRT) or a bicycle ergometer (ITCT). Blood samples were obtained before (D0), on day 5(D5) and after 10 d (D11) of ITRT and ITCT. A significant increase in the CD4+/CD8+ ratio occurred at D5 compared with D0 and D11. The CD4+/CD8+ ratio was significantly lower during ITRT compared with ITCT at D11. The number of circulating CD3+, CD4+, and CD8+ cells were significantly reduced at D11 compared with D0. In conclusion, 10 d of IT resulted in a significant reduction in the number of circulating T cells independent of the training mode and a reduction in the CD4+/CD8+ ratio for ITRT but not for ITCT.
OBJECTIVE: To compare the effect of walking training on a treadmill with body weight support (BWS) and walking training on the ground at an early stage of rehabilitation in patients with hemiparesis after stroke. DESIGN: Randomized controlled experimental study. SETTING: Multicentre design; three departments of rehabilitation medicine. SUBJECTS: Seventy-three consecutive first stroke patients admitted to a rehabilitation clinic were randomized into a treatment group and a control group. INTERVENTIONS: The treatment group received walking training on a treadmill with BWS for 30 minutes, 5 days a week. The control group received walking training according to the Motor Relearning Programme (MRP) on the ground for 30 minutes 5 days a week, not including treadmill training. During the time in the rehabilitation department (about two months), all patients in the study also received professional stroke rehabilitation besides the walking training in the two groups. MAIN OUTCOME MEASURES: Functional Independence Measure (FIM), walking velocity for 10 m, Functional Ambulation Classification (FAC), Fugl-Meyer Stroke Assessment and Berg's Balance Scale. The assessments were performed at admission, at discharge and at 10-month follow-up. RESULTS: There were no statistically significant differences between the groups at discharge or at the 10-month follow-up with regard to FIM, walking velocity, FAC, Fugl-Meyer Stroke Assessment, and Berg's Balance Scale. Patients in both groups improved in these variables from admission to the 10-month follow-up. CONCLUSIONS: Treadmill training with BWS at an early stage of rehabilitation after stroke is a comparable choice to walking training on the ground.
BACKGROUND: This study was undertaken to investigate operating room performance of surgical residents, after participating in the Eindhoven virtual reality laparoscopic cholecystectomy training course. This course is the first formal surgical resident trainings course, using a variety of complementary virtual reality (VR) skills training simulation in order to prepare surgical residents for their first laparoscopic cholecystectomy. The course was granted EAES certification. METHODS: The four-day course is based on multimedia and multimodality approach. A variety of increasingly difficult simulation training sessions, next to intimate focus-group "knowledge sessions" are included. Both basic and procedural VR simulation is featured, using MIST-VR and the Xitacts' LapChol simulation software. The operating room performance of twelve surgical residents who participated in the course and twelve case-control counterparts were compared. The case-control group was matched for clinical number laparoscopic cholecystectomy performance (maximum of 4 procedures). Two observers analyzed a randomly mixed videotape, featuring the part of the "clip-and-cut" procedure of the laparoscopic cholecystectomy, and were blinded for participants' group status. Structured questionnaires including multiple observation scales were used to assess performance. RESULTS: Residents of both the experimental and control group did not differ in demographic parameters, except for number of laparoscopic cholecystectomies in favor of the control group (p-value 0.008). Both observers judge the experimental group to perform significantly better (p-value 0.004 and 0.013). Experimental group residents valued their course highly in terms of their laparoscopic surgical skills improvement and the use of VR simulators in the surgical curriculum. CONCLUSIONS: The Eindhoven Virtual Reality laparoscopic cholecystectomy training course improves surgical skill in the operating room above the level of residents trained by a variety of other training methods.
Obtaining training data for constructing artificial neural networks (ANNs) to identify microbiological taxa is not always easy. Often, only small data sets with different numbers of observations per taxon are available. Here, the effect of both size of the training data set and of an imbalanced number of training patterns for different taxa is investigated using radial basis function ANNs to identify up to 60 species of marine microalgae. The best networks trained to discriminate 20, 40 and 60 species respectively gave overall percentage correct identification of 92, 84 and 77%. From 100 to 200 patterns per species was sufficient in networks trained to discriminate 20, 40 or 60 species. For 40 and 60 species data sets an imbalance in the number of training patterns per species always affected training success, the greater the imbalance the greater the effect. However, this could be largely compensated for by adjusting the networks using a posteriori probabilities, estimated as network output values.
This study involved a retrospective examination of physical fitness, training outcomes, and injury rates among personnel in the Fitness Training Unit (FTU). Personnel were assigned to the FTU based on low performance on push-ups, sit-ups, and/or a 1-mile run (N = 44 men, 95 women) and received an augmented physical fitness program before basic combat training (BCT). They were compared with 712 men and 379 women who took the same test but were not assigned to the FTU and went directly to BCT. FTU and non-FTU personnel trained in the same battalions. Army Physical Fitness Test scores and BCT outcomes (discharged or completed BCT in 8 weeks) were obtained from unit training records. Injuries during BCT were documented from a review of the medical records. On entry to BCT, FTU women had similar 2-mile run times compared with non-FTU women (21.6 vs. 21.5 minutes, respectively; p = 0.86); FTU men were considerably slower on the 2-mile run than non-FTU men (20.3 vs. 17.3 minutes; p < 0.01). FTU women and non-FTU women had similar graduation success (60% vs. 68%, respectively; p = 0.14) and time-loss injury rates (1.3 vs. 1.4 people injured/100 person-days, respectively; p = 0.90). FTU men were less likely to graduate than non-FTU men (55% vs. 82%; p < 0.01) and more likely to suffer a time-loss injury (1.2 vs. 0.7 people injured/100 person-days; p < 0.01). Efforts should be directed toward providing a sufficient training stimulus to improve the aerobic fitness level of men (as well as women) in the FTU.
AIM: To identify the magnitude and sources of error involved in simply quantifying the workload of a group of Thoroughbred racehorses in training. METHODS: Data were obtained from seven 2-year-old fillies trained for 13 weeks on sand and grass tracks at various cantering velocities, and at the gallop in the last 4 weeks. Four fillies completed training and comprised a 'high exercise intensity' subgroup; three fillies did not complete all gallops due to lameness or injury and comprised a 'medium exercise intensity' subgroup. The trainer recorded the distance, time, track used, and subjective gait (SG; viz canter, 1/4-pace, 1/2-pace and gallop) of each horse each day. Data were analysed to describe the training programme and sources of variation in workload. A cumulative workload index (CWI) was devised to simply express distance and velocity aspects of the training programme. RESULTS: The magnitude of errors in measurement of timing and distance were small but significant (<0.8%, p=0.01). SG was an inaccurate descriptor of velocity. Mean velocity of 1/2-pace decreased from 8.92 (SE 0.049) in Weeks 6-8 to 6.33 (SE 0.061) m/sec after the start of galloping sessions in Week 9 (p=0.01). Track surface had a significant effect on the velocity of 1/2-pace (p=0.001). The fastest velocity was recorded on the grass (9.06, SE 0.292 m/sec), followed by 'plough' (8.23, SE 0.152 m/sec), and sand (7.90, SE 0.132 m/sec) tracks. The CWI of the horses ranged between 1,085,000 and 1,634,000 (mean=1,428,000; SE 78,000). The average exercise intensity per week was 110,000 (SE 1,048). There were no significant differences between high and medium exercise intensity subgroups for the canter and 1/4-pace. The high exercise subgroup had a greater CWI for the 1/2-pace (839,000 vs 559,000; p=0.004), gallop (71,000 vs 31,000; p=0.001), and total index (1,580,000 vs 1,242,000; p=0.001). CONCLUSIONS: The workload history of a horse can be accurately described using an index based on manual measurement of the time and distance worked. CLINICAL RELEVANCE: Accurate and precise data on the training programme of performance horses are likely to enable greater differentiation of aspects of workload which are associated with both performance and injury.
UNLABELLED: Pain coping skills training (PCST) has been shown to produce immediate improvements in pain and disability in rheumatoid arthritis (RA). However, some patients have difficulty maintaining these gains. This study compared a conventional PCST protocol with a PCST protocol that included maintenance training (PCST/MT). Patients with RA (n = 167) were randomly assigned to either conventional PCST, PCST/MT, arthritis education control, or standard care control. Daily data were collected on joint pain, coping, coping efficacy, and mood. Multilevel analyses showed that at posttreatment, conventional PCST was superior to all other conditions in joint pain, coping efficacy, and negative mood, whereas PCST/MT was superior to all other conditions in emotion-focused coping and positive mood. At 18 months follow-up, both PCST conditions were superior to standard care in joint pain and coping efficacy. Interpretation of follow-up outcomes was limited by higher dropout rates in the 2 PCST groups. For RA, a maintenance training component does not appear to produce significant improvements over conventional PCST. PERSPECTIVE: This article reports a trial evaluating a conventional pain coping skills training protocol and a similar protocol that included a maintenance training component. Overall, results indicate similar results for both the conventional and the modified protocols.
Spontaneous analogical transfer is the use of information from one problem to solve another problem, without an explicit hint to use the previous information. The results of five experiments were that if subjects tried to solve a training problem before hearing its solution, or tried to explain a training story's solution before hearing the correct explanation, spontaneous transfer was more likely than it was if subjects had studied the same training passage for memory before hearing its solution or explanation. The advantage of problem-oriented processing over memory-oriented processing occurred even though solution attempts nearly always failed, and the advantage was not reduced if the target problem was tested 15 min later rather than immediately after training. We propose that problem-oriented processes performed at study are appropriate processes to use at test. Further support for the account comes from subjects' memory for the training passages; the advantage for problem-oriented processing on solution tasks was mirrored by an equally substantial advantage for the memory-oriented subjects on a recall task.