Showing papers on "Interval training published in 2003"

Endurance Training and Aerobic Fitness in Young People

Abstract: Training-induced adaptations in aerobic fitness have been extensively studied in adults, and some exercise scientists have recommended similar training programmes for young people. However, the subject of the response to aerobic training of children and adolescents is controversial. The effects of exercise training on prepubertal children are particularly debatable. The latter may be partly explained by different training designs, which make comparisons between studies very problematic. We have analysed the procedures applied to protocol design and training methods to highlight the real impact of aerobic training on the peak oxygen uptake (V-dotO2) of healthy children and adolescents. In accordance with previously published reviews on trainability in youngsters, research papers were rejected from the final analysis according to criteria such as the lack of a control group, an unclear training protocol, inappropriate statistical procedures, small sample size, studies with trained or special populations, or with no peak V-dotO2 data. Factors such as maturity, group constitution, consistency between training and testing procedures, drop out rates, or attendance were considered, and possible associations with changes in peak V-dotO2 with training are discussed. From 51 studies reviewed, 22 were finally retained. In most of the studies, there was a considerable lack of research regarding circumpubertal individuals in general, and particularly in girls. The results suggest that methodologically listed parameters will exert a potential influence on the magnitude of peak V-dotO2 improvement. Even if little difference is reported for each parameter, it is suggested that the sum of errors will result in a significant bias in the assessment of training effects. The characteristics of each training protocol were also analysed to establish their respective potential influence on peak V-dotO2 changes. In general, aerobic training leads to a mean improvement of 5-6% in the peak V-dotO2 of children or adolescents. When only studies that reported significant training effect were taken into account, the mean improvement in peak V-dotO2 rose to 8-10%. Results suggested that intensities higher than 80% of maximal heart rate are necessary to expect a significant improvement in peak V-dotO2. There is clearly a need for longitudinal or cross-sectional studies that investigate the relationship between maturity and training with carefully monitored programmes. Further research is also needed to compare interval training and continuous training.

Effect of training intensity on physical capacity, lipid profile and insulin sensitivity in early rehabilitation of spinal cord injured individuals

Abstract: Study design: Pre–post training intervention. Objectives: To evaluate the effect of training intensity on physical capacity, lipid profile and insulin sensitivity in early rehabilitation of spinal cord injured (SCI) patients, and to assess the correlation between peak aerobic capacity (VO2Peak) and insulin sensitivity. Setting: Spinal Cord Rehabilitation Unit, Sunnaas Hospital, Nesoddtangen, Norway. Method: Six recently injured SCI individuals participated in the arm training intervention and were randomly admitted to a high-intensity (HI; 70–80% heart rate reserve (HRR)) and low-intensity (LI; 40–50% HRR) group. The 1 h interval training consisted of 3 min exercise bouts interspersed with 2 min of rest, three times a week for 8 weeks. In addition, a correlation coefficient was obtained between VO2Peak and insulin sensitivity in 11 SCI patients. Results: The 8-week training program resulted in a significant increase in VO2Peak and maximal power output (POMax) for the group as a whole (P<0.05). VO2Peak increased significantly more and total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) ratio and triglycerids decreased significantly more in the HI group than in the LI group (P=0.05). Training-induced changes in insulin sensitivity were significantly different between the groups (P=0.05), which was due to a nonsignificant decline in insulin sensitivity in the HI group and a nonsignificant improvement in the LI group. A significant positive correlation was found between VO2peak and insulin sensitivity (r=0.68, P=0.02). Conclusion: The interval arm training protocol as used in the present study enables recently injured SCI patients to do substantial work at a relatively high intensity. Results indicate that improvements in physical capacity and lipid profile were more pronounced in response to high-intensity training. The significant correlation between maximal oxygen consumption and insulin sensitivity indicates that, as in the able-bodied population, peak aerobic capacity is a predictive value with regard to insulin sensitivity in SCI. Future studies with larger groups assessing the role of exercise intensity on insulin sensitivity in SCI are suggested.

Jog-walk training in cardiorespiratory fitness of adults with Down syndrome.

Abstract: The purpose of this study was to evaluate the effects of an aerobic training program on adults with Down syndrome. 25 male adults with Down syndrome (M age = 24.6 yr., [Qs = 45-60) participated in a 12-wk. exercise training study. Subjects were assigned to an experimental group (n = 15) and a control group (n = 10). Pre- and posttraining treadmill tests were performed to determine the following peak physiological parameters: heart rate (HR peak), peak minute ventilation (V(E) peak), peak oxygen consumption (VO2 peak, absolute and relative), and time to exhaustion (min.). The experimental group underwent a 12-wk. interval training program. The control group received no structured exercise training during this period. Following the 12-wk. training program, significant improvements (p < .05) in peak physiological parameters were seen for the experimental group for VO2 peak (both relative and absolute). V(E) peak, and time to exhaustion. No significant improvements in peak physiologic parameters were seen in the control group. Consistent with prior research using similar subjects, we concluded that adults with Down syndrome are able to improve their aerobic capacity when performing a systematic and well-designed aerobic training program.

Evaluation of stress responses to interval training at low and moderate altitudes.

Abstract: NIESS, A M, E FEHRENBACH, G STROBEL, K ROECKER, E M SCHNEIDER, J BUERGLER, S FUSS, R LEHMANN, H NORTHOFF, and H-H DICKHUTH Evaluation of Stress Responses to Interval Training at Low and Moderate Altitudes Med Sci Sports Exerc, Vol 35, No 2, pp 263–269, 2003PurposeThe purpose of

Comparison of the influence of volume-oriented training and high-intensity interval training on serum homocysteine and its cofactors in young, healthy swimmers

Abstract: Background: Since homocysteine (Hcy) is a risk factor for cardiovascular and other diseases, it is important to know how exercise can modify it. Previous studies have suggested that endurance training influences Hcy. However, little is known about the effect of training intensity on Hcy. Materials and Methods: We investigated Hcy, vitamin B 12 , vitamin B 6 , folate and methylmalonic acid (MMA) before and after 3 weeks of volume-oriented training (VOL) (30 km/week) and high-intensity interval training (HIT) (20 km/week) in 20 young swimmers (16±2 years). Afterward, the athletes completed 5 days of recovery training. Results: The training induced a Hcy increase in HIT and VOL (6.47±0.95 μmol/l vs. 7.44±1.17 μmol/l and 7.33± 1.92 μmol/l vs. 8.28±1.42 μmol/l, respectively) that persisted during the recovery period (8.02±1.69 μmol/l and 8.00±1.81 μmol/l, respectively). Vitamin B 12 was unchanged after the training (539±166 ng/l vs. 556±192 ng/l and 480±144 ng/l vs. 491±124 ng/l, respectively) but decreased during the recovery period (459±134 ng/l and 451±116 ng/l, respectively). Folate showed an increase during the training (9.07 ±2.01 μg/l vs. 11.71±4.08 μg/l and 10.34±2.32 μg/l vs. 11.13± 4.64 μg/l, respectively), which was reversible by the end of the recovery training (8.57±1.98 μg/l and 9.60±2.38 μg/l, respectively). Vitamin B 6 and MMA did not change. For none of the measured parameters were there significant differences between HIT and VOL. Conclusion: Three weeks of strenuous swimming caused a prolonged Hcy increase, which was accompanied by changes in vitamin B 12 and folate. The magnitude of these effects was not influenced by the training intensity.

The effects of interval training on oxygen pulse and performance in supra-threshold runs.

Abstract: The aim of this study was to examine (i) the effects of a severe interval training period on oxygen pulse kinetics (O 2 -p, the ratio between VO 2 and heart rate), and (ii) to study the consequences of these effects on the variation of performance (time to exhaustion) during severe runs. Seven athletes were tested before and after an eight-weeks period of a specific intermittent training at vω50, i.e., the intermediate velocity between the lactate threshold (vLT) and the velocity associated with VO 2max (vVO 2max). During the test sessions, athletes performed an incremental test and an all-out test at the pretraining vω50. After the training period they also completed an additional all-out test at the posttraining vω50 (vω50bis). Results showed that after training there was i) an increase in the O 2 -p maximal value during the incremental test (22.7 ± 1.5 mlO 2.b -1 vs. 20.6 ± 1.5 mlO 2.b -1; p < 0.04), ii) a decrease in the time to reach the O 2 -p steady state (TR O2-p) at the same absolute vω50 (33 ...

Whichever the initial training status, any increase in velocity at lactate threshold appears as a major factor in improved time to exhaustion at the same severe velocity after training.

Abstract: The first purpose of this study was to assess the eventual training adaptations in the time to exhaustion at the same severe velocity occurring after severe interval-training programs in few- and well-trained subjects. In the event of such training adaptations, the second purpose was to identify the discriminant factors of performance improvement according to the initial training status. Seven few- and six well-trained subjects performed: firstly, an incremental test to determine the maximal oxygen consumption (VO2max), the energy cost of running (ECR), the velocity associated with the achievement of VO2max (vVO2max) and the lactate threshold (LT expressed in VO2, km x h(-1), % vVO2max); secondly, an all-out test at the velocity corresponding to the midway between vLT and vVO2max (vdelta50) to determine the time to exhaustion (tmax); such tests were carried out before and after 4- and 8-week severe interval-training programs. In the few-trained subjects, all factors of performance (i.e., VO2max, ECR, vVO2max, LT expressed in VO2, km x h(-1), % vVO2max) and tmax at the pre-training vdelta50 were improved after training (+8, -8, +7, +9, +14, +6% and +79%, respectively); only the increase in vLT was related to the one in tmax (r = 0.714, p < or = 0.05, n = 7). In the well-trained subjects, only vVO2max was improved (+3%) due to the decrease in ECR (-3%), tmax at the pre-training vdelta50 did not vary after training; only the three subjects (over six) who improved their vLT (+0.5, +0.5, +0.8 km x h(-1), respectively) improved their tmax (+10, +24, +101%, respectively) (r = 0.895, p < or = 0.01, n = 6). So, whichever the initial training status, any training-induced adaptation in vLT appeared as a major factor of performance improvement especially at supra-LT velocities.

Recovery after total hip joint arthroplasty in elderly patients with osteoarthritis: positive effect of upper limb interval-training.

Abstract: Objective To evaluate the influence of an interval training program for the upper limbs on cardiorespiratory fitness and walking ability in elderly patients after total hip joint arthroplasty. Design A randomized controlled trial. After surgery, control and training groups started general rehabilitation. Training group combined it with an arm-interval exercise program (3 sessions of 30 minutes per week, for 6 weeks). Subjects Patients were assigned randomly to control (n = 7) and training groups (n = 7). Methods Incremental exercise tests were carried out until exhaustion on an arm crank ergometer 1 month before and 2 months after surgery. A 6-minute walk test was also performed 2 months after surgery. Results VO2 peak increased significantly in the training group (p = 0.0424) and did not change in the control group. The difference in VO2 peak change between the groups was significant (p = 0.0362, +19.2% in the training group and -3.5% in the control group). In the walking test the training group covered a significantly longer distance than did the control group (p = 0.0055, 396.4 metres and 268.1 metres, respectively). Conclusion These results stress the importance of physical training in a rehabilitation program after total hip joint arthroplasty and this should be considered for improving the current practices in rehabilitation.

The effect of rest periods on energy system contribution during interval swimming

Abstract: The purpose of this study was to investigate the effect of rest periods on energy system contribution during interval swimming and whether the energy system contribution varied depending on the swimmer's specialty, such as swimmers who specialize in the 100 m or 200 m. Seven highly-trained male varsity swimmers performed three different tests: a 10-min continuous test (CON), 10 × 1-min interval test with rest periods of 20 s (INT20) and 10 × 1-min interval test with rest periods of 30 s (INT30). Swimming velocity during all tests was set to maintain a blood lactate of 4 mM determined by progressive swimming. The relative aerobic and anaerobic energy system contribution was evaluated from accumulated oxygen uptake and oxygen deficit. Aerobic energy system contribution in CON, INT20, and INT30 was 93.3 ±1.1, 81.0 ±10.4, and 67.4 ±8.5%, and anaerobic contribution was 6.7 ±1.1, 19.0 ±10.4, and 32.6 ±8.5%, respectively. There were significant differences (p

Cardiopulmonary exercise test and heart rate variability in patients with congestive heart failure who underwent physical rehabilitation

Abstract: Physical rehabilitation of patients with heart diseases is a well-known therapeutical method used in patients with heart failure. However there is no consensus regarding rehabilitation program for these patients. The aim of this study was to assess tolerance of physical exercise and parameters of heart rate variability in patients with chronic heart failure who were exercised using different models of training. 42 patients (mean age 55.9 +/- 8.2) with chronic heart failure (NYHA class II and III) were included into this study. They were divided randomly into three groups, each number 14 patients: group A--patients who were trained according to model with progressive increase of workload, group B--patients with interval training, and group C--patients who were not trained at all. The study groups did not differ in average age, BMI, NYHA class, or pharmacological treatment. All patients from groups A and B were rehabilitated during six months, 3 times per week for 1.0 hour each time. All patients were submitted to the following examinations before and after six months of training: echocardiography, cardiopulmonary exercise test and 24-hour ECG recording with evaluation of time-domain HRV parameters. In groups A and B we observed an improvement in exercise capacity, which was more pronounced in group A. This improvement was observed as increase in total exercise time when compared with group B and C (839.1 +/- 98.3 sec vs 472.4 +/- 39.7 sec vs 347.92 +/- 61.0 sec respectively at p < 0.0001), and increase in workload (6.28 +/- 0.8 MET vs 3.9 +/- 0.2 MET vs 2.6 +/- 0.63 MET respectively in the study groups). We also found improved cardiopulmonary exercise test. After six months we observed significant differences in all parameters between group A and C, and in VO2max between group B and C (16.5 +/- 1.9 vs 14.1 +/- 1.9 ml/kg/min, p < 0.01) and in VE/VCO2 (37.8 +/- 4.2 vs 40.4 +/- 6.7 l/min, p < 0.01). After 6 months we also found significant differences between group A and B in HRV parameters which reflect total activity of the autonomous system (SDNN--174.0 vs 96.0 at p < 0.0001; SDANNI--138.1 vs 83.2 at p < 0.0001) and between group A and group C (174.0 vs 78.4, p < 0.0001). In parameters that reflect parasympathetical activity of the autonomous system there were significant changes between group A and group B (rMSSD--42.5 vs 24.7 at p < 0.001, pNN50 18.5 vs 4.2, p < 0.001) and between group A and group C (rMSSD--42.5 vs 16.7 at p < 0.001, pNN50 18.5 vs 4.2 at p < 0.001). Regular exercise training in patients with chronic heart failure, using especially the progressive increase of workload, improves exercise capacity without any negative influence on systolic and diastolic function parameters of the left ventricle. In these patients we may also observe beneficial changes in HRV parameters.

Effects of high intensity aerobic interval training in water polo players

Abstract: Even though water polo has been the fi rst team sport included in The Olympic Games (Paris, 1900), there has been very little scientifi c information of water polo training, and practice demands and its related effects found in the literature. The same does not occur with swimming. A lot of information can be found in scientifi c publications. That kind of information is relevant to an effi cient training program frame. As some training methods are similar to swimming and water polo, it is possible to firecommendations for employing swimming markers in water polo, which it is not well accepted by water polo coaches, since there are differences between those sports. Attempting to diminish this lack of informa- tion, the purpose of this study was investigate water polo players' specifi c responses to certain interval-training loads, a common water polo training method. One group of well-fi tted male water polo players (n = 10; age = 20.1 + 2.33 years; weight = 78.9 + 15.48 kg; height = 177.2 + 7.98 cm) was submitted to interval training frame, called by VALDIVIELSO as high intensity aerobic, with 2 sets of 10 reps of 100 meters, all of them done in a front crawl style, 2 minutes rest interval between sets and 20 seconds between reps, maintaining a mean speed between 75 and 95% of 100 meters crawl maximum speed, measuring blood lactate (La), heart rate (HR) and rate of perceived exertion (RPE).The results of this study (La = 10.1 + 1.87 mmol/l; HR = 167.4 + 9.16 bpm and RPE = 18 + 1.0) shows that this interval training frame has a higher demand in water polo players than in swimmers, but also give us some fi rst markers to prescribe and control endurance's training to water polo players.

Efeitos da aplicação de treinamento intervalado aeróbico intenso em atletas de water polo

Abstract: Effects of high intensity aerobic interval training in water polo players Even though water polo has been the first team sport included in The Olympic Games (Paris, 1900), there has been very little scientific information of water polo training, and practice demands and its related effects found in the literature The same does not occur with swimming A lot of information can be found in scientific publications That kind of information is relevant to an efficient training program frame As some training methods are similar to swimming and water polo, it is possible to find recommendations for employing swimming markers in water polo, which it is not well accepted by water polo coaches, since there are differences between those sports Attempting to diminish this lack of information, the purpose of this study was investigate water polo players’ specific responses to certain interval-training loads, a common water polo training method One group of well-fitted male water polo players (n = 10; age = 201 ± 233 years; weight = 789 ± 1548 kg; height = 1772 ± 798 cm) was submitted to interval training frame, called by VALDIVIELSO as high intensity aerobic, with 2 sets of 10 reps of 100 meters, all of them done in a front crawl style, 2 minutes rest interval between sets and 20 seconds between reps, maintaining a mean speed between 75 and 95% of 100 meters crawl maximum speed, measuring blood lactate (La), heart rate (HR) and rate of perceived exertion (RPE)The results of this study (La = 101 ± 187 mmol/l; HR = 1674 ± 916 bpm and RPE = 18 ± 10) shows that this interval training frame has a higher demand in water polo players than in swimmers, but also give us some first markers to prescribe and control endurance’s training to water polo players

A graphical model for interval training

Abstract: t has often been demonstrated that greater improvements in key performance factors (anaerobic capacity, maximal aerobic power [MAP] and aerobic endurance) in most of the so called ‘aerobic’ sports such as cross country, middle and long distance running can be achieved through training programmes that include intermittent sessions. In fact, as shown in Table 1, when doing continuous exercise, one cannot sustain intensity in the optimal development zone of these key performance factors for very long. It is exactly because it enables an athlete to perform a greater amount of work at a given elevated relative intensity that interval training is frequently preferred to continuous training.

Kurz- und langfristige Effekte der Fütterung von Trockenschnitzelexpandat auf die metabolischen Reaktionen und die Leistungsfähigkeit beim arbeitenden Pferd

Abstract: This study investigated the effect of partial replacement of a pelleted concentrate with molassed sugar beet pulp on metabolic parameters and performance in exercising horses. Six Standardbred horses entered the study in a balanced 3 x 3 crossover design. The horses in group A (n = 3) were fed a pelleted concentrate during the first experimental period, and the horses in group B (n = 3) received an isoenergetic meal designed to replace 65 % of the concentrate´s digestible energy (MJ DE) with molassed sugar beet pulp. In the second experimental period, feeding regimes were crossed over. Both experimental periods consisted of eight long-term and eight interval exercise sessions performed every other day on a high speed treadmill. At the beginning and at the end of each experimental period, a standardized exercise test was performed and evaluated. Throughout the study, the following parameters were measured at timed intervals: body weight, rectal body temperature, sweat loss, heart rate, total plasma protein, insulin, glucose, lactate, free fatty acids, sodium, potassium and chloride. Mean body weight of all horses increased from 406 ± 41 kg at the beginning of the study to 421 ± 56 kg at the end of the experiment (p < 0.05). No significant difference in body weight between the two diets was seen. There were no significant differences in rectal body temperature between group A and group B. Exercise resulted in an increase from 37.6 ± 0.2 °C up to 41.4 ± 0.3 °C (p < 0.05). Sweat losses occuring during the training sessions and standardized exercise tests reached maximal concentrations of 2 % of the total body weight (no significant difference between the diets). Heart rate sharply increased from 117 ± 9 beats per minute to 204 ± 5 beats per minute during the standardized exercise tests. In response to the long-term exercise sessions, mean heart rate raised slightly to 136 ± 8 beats per minute. The interval exercise sessions caused peak heart rates of approximately 208 beats per minute during the gallop periods and a decrease during the walking phases (below 100 beats per minute). The different diets did not affect the heart rate. While a 7.2 % rise of total plasma protein was detected during the standardized exercise tests, the concentrations during the long-term exercise sessions changed just moderately. The gallop phases of the interval exercise sessions increased plasma protein concentrations, and a decrease was noticed during the walking periods. The increase of total plasma protein was significant, but did not vary between the diets. Plasma insulin did not differ between the diets either. Concentrations decreased during the standardized exercise tests and the interval training sessions (p < 0.05), but did not change during the long-term exercise sessions (n.s.). Plasma glucose concentrations increased during exercise (p < 0.05). Compared to the values at rest, glucose concentrations were doubled during the standardized exercise tests and the interval training sessions. Long-term exercise sessions only moderately increased plasma glucose. The two different diets did not affect the plasma glucose levels. Blood lactate did not change either with the different diets (n.s.). The exercise induced increase (p < 0.05) was higher during the standardized exercise tests and the gallop phases of the interval exercise sessions compared to the long-term training sessions. According to this study the rise of the free fatty acids depended on type of exercise. Concentrations increased from about 100 µmol/l to 150-250 µmol/l during the standardized exercise tests and the interval training sessions, whereas long-term exercise sessions forced peak free fatty acid concentrations of 640 µmol/l and above (p < 0.05). The difference between the two diet-groups was not significant. Blood sodium and potassium levels peaked during the standardized exercise tests and remained constant at that level during the long-term training sessions. The blood parameters increased during the gallop periods of the interval exercise sessions but returned to pre-exercise concentrations during the walking phases. Blood chloride concentrations decreased during both the standardized exercise tests and the two types of exercises. Dietary effects were not observed. In conclusion, no detrimental effects on metabolic parameters and performance in exercising horses fed with molassed sugar beet pulp were found. The speculated positive effects on the horse´s hydration status could not be confirmed.