Pre-radiotherapy daily exercise training in non-small cell lung cancer: A feasibility study

AimTo examine the feasibility of an individual, supervised, structured moderate-to-high intensity cycle ergometer exercise training immediately before radiotherapy in patients undergoing concomitant chemoradiotherapy for locally advanced non-small cell lung cancer (NSCLC).BackgroundLung cancer is the most common form of cancer. Despite significant advancements in therapy and supportive care it is still the leading cause of cancer-related death worldwide.Materials and methodsRandomized controlled study design; patients with NSCLC receiving concomitant chemoradiotherapy were recruited and randomly assigned to either the exercise (EXE) or the control (CON) group. Exercise training consisted of 20 min moderate-to-high intensity aerobic interval training 5 times per week (Mon–Fri) prior to radiotherapy. Secondary outcomes were assessed at baseline and after 7 weeks: peak oxygen consumption (VO_2peak), functional capacity (6MWD), pulmonary function (FEV1), psychosocial parameters (quality of life (FACT-L), anxiety and depression (HADS)) and cancer-related side effects (reported daily).ResultsFifteen patients were included. All patients completed a baseline test, while 13 patients were eligible for a posttest. The recruiting rate was 44.1% and the overall attendance rate to exercise was 90.0% with an adherence rate to full exercise participation of 88.1%. No adverse events or any unexpected reactions were observed during the exercise sessions. No significant differences were observed within or between groups from baseline to post intervention in any of the secondary outcomes.ConclusionThis study demonstrated ‘proof of principle’ that daily moderate-to-high intensity cycle ergometer exercise was feasible, safe and well tolerated among newly diagnosed patients with locally advanced NSCLC undergoing concomitant chemoradiotherapy. Larger randomized controlled trials are warranted.     

A study of physical demands in riding

Thirteen experienced riders and three elite riders underwent bicycle ergometer tests at submaximal and maximal workloads. Oxygen uptake, pulmonary ventilation and heart rate were also studied during riding at a walk, a trot and a canter. The mean maximal oxygen uptake of the experienced riders in the ergometer test (2.71 . min-1) was superior to the average maximal oxygen uptake of other groups of the same age and sex. The average oxygen uptake of the experienced riders in trot sitting was 1.701 . min-1, trot rising 1.681 . min-1 and in canter 1.801 . min-1. The experienced riders used at least 60% of their maximal aerobic power in trot and canter, which is an exercise intensity that may induce some training effect. Two elite riders consistently had lower oxygen uptakes in riding than the other riders. The heart rate -- oxygen uptake relationships in riding and in the ergometer tests were similar, except during trot sitting when the heart rate tended to be higher, indicating a larger share of static muscle contraction in this gait. Static muscle strength was measured in nine riders and seven non-riders. Six muscle groups were investigated, but no significant difference in muscle strength could be demonstrated between riders and controls.     

Quantitation of resistance training using the session rating of perceived exertion method

The purpose of this study was to apply the session rating of perceived exertion (RPE) method, which is known to work with aerobic training, to resistance training. Ten men (26.1 +/- 10.2 years) and 10 women (22.2 +/- 1.8 years), habituated to both aerobic and resistance training, performed 3 x 30 minutes aerobic training bouts on the cycle ergometer at intensities of 56%, 71%, and 83% Vo(2) peak and then rated the global intensity using the session RPE technique (e.g., 0-10) 30 minutes after the end of the session. They also performed 3 x 30 minutes resistance exercise bouts with 2 sets of 6 exercises at 50% (15 repetitions), 70% (10 repetitions), and 90% (4 repetitions) of 1 repetition maximum (1RM). After each set the exercisers rated the intensity of that exercise using the RPE scale. Thirty minutes after the end of the bout they rated the intensity of the whole session and of only the lifting components of the session, using the session RPE method. The rated intensity of exercise increased with the %Vo(2) peak and the %1RM. There was a general correspondence between the relative intensity (%Vo(2) peak and % 1RM) and the session RPE. Between different types of resistance exercise at the same relative intensity, the average RPE after each lift varied widely. The resistance training session RPE increased as the intensity increased despite a decrease in the total work performed (p < 0.05). Mean RPE and session RPE-lifting only also grew with increased intensity (p < 0.05). In many cases, the mean RPE, session RPE, and session RPE- lifting only measurements were different at given exercise intensities (p < 0.05). The session RPE appears to be a viable method for quantitating the intensity of resistance training, generally comparable to aerobic training. However, the session RPE may meaningfully underestimate the average intensity rated immediately after each set.     

Frequency and duration of interval training programs and changes in aerobic power.

This study was designed to ascertain whether 7- and 13-wk interval training programs with training frequencies of 2 days/wk would produce improvement in maximal aerobic power (VO2max) comparable to that obtained from 7- and 13-wk programs of the same intensity consisting of 4 training days/wk. Sixty-nine young healthy college males were used as subjects. After training, there was a significant increase in VO2max (bicycle ergometer, open-circuit spirometry) that was independent of both training frequency and duration. However, there was a trend for greater gains after 13 wk. Maximal heart rate (direct lead ECG) was significantly decreased following training, being independent of both training frequency and duration. Submaximal VO2 did not change with training but submaximal heart rate decreased significantly with greater decreases the more frequent and longer the training. Within the limitations of this study, these results indicate that: 1) maximal stroke volume and/or maximal avO2 difference, principle determinants of VO2max, are not dependent on training frequency nor training duration, and 2) one benefit of more frequent and longer duration interval training is less circulatory stress as evidenced by decreased heart rate, during submaximal exercise.     

The durations of the phases and periods of the cardiac cycle in athletes as dependent on the specific type of training

Polycardiography was used to analyze cardiac cycle phases in young track athletes during a two-year training cycle. The subjects were examined in the state of relative muscular rest and during moderate bicycle ergometer exercise. It was found that track training leads to a decrease in the heart rate and regulatory myocardial hypodynamic syndrome. Adaptive rearrangements in myocardial contractility were observed; they depended on the age of athletes and the type of training during the training macrocycle. The performance of the test with a moderate intensity was accompanied by a hyperdynamic syndrome, the degree of its manifestation depending on the age of the subject and the exercise intensity.     

长期中小强度有氧运动对大鼠左心室肌蛋白质组差异表达的影响*

目的:探讨长期中小强度有氧运动对大鼠左室肌蛋白质组差异性表达的影响,筛选出对中小强度有氧运动刺激敏感的目标蛋白质,丰富运动健身的基础理论及为慢性心血管疾病的康复治疗提供新的思路和实验依据。方法:20只雄性SD大鼠随机分为运动组(E组)和对照组(C组)(n=10)。建立大鼠长期中小强度有氧运动跑台训练模型,采用双向凝胶电泳(2-DE)对大鼠左心室肌全蛋白样品进行分离。采用串联飞行时间质谱蛋白质仪对部分分离后差异表达量上调大于5倍或下调超过80%的蛋白质点进行质谱鉴定。结果:与C组比较,E组大鼠心脏重量指数(HWI)增加了32.0%,具有显著性差异(P＜0.05);与C组比较,E组有71个蛋白质点表达上调≥2倍或下调≥50%,对4个表达上调≥5倍或下调大于等于80%的蛋白质点进行质谱鉴定,鉴定出3个蛋白质和1个未知蛋白质。结论:长期中小强度有氧运动后,大鼠心脏发生了良好的适应性改变;大鼠左心室肌蛋白质组发生了明显变化,长期中小强度有氧运动能有效增强大鼠心肌抗氧化能力。     

Aerobic capacity of forestry workers and physical demands of forestry operations.

The present study aimed at evaluating the aerobic capacities of forestry workers and the physical demands of their occupation. A submaximal cycle ergometer test was conducted on 22 male forestry workers and 15 male sedentary office workers aged 40-59 years. The slope of the regression line of heart rates on given exercise intensities was significantly smaller in the forestry workers than in the office workers. The mean heart rate of the forestry workers was 9 beats.min-1 less than that of the office workers at the initial exercise intensity of 50 W. This difference increased to 25 beats.min-1 at 175 W. For 6 of the 22 forestry workers, heart rates were recorded continuously during a usual workday. The metabolic rates, as multiples of basal metabolic rate (in met) of various forestry activities were estimated from the average heart rate during the activity of interest and a predicted maximal oxygen consumption of the subject obtained from a submaximal cycle ergometer test. The mean energy expenditure was 4.5 met with a range of 3.3-6.3 met for an average of 509 min at a worksite. These results indicated that the forestry workers had high aerobic capacities and this was ascribed to the high physical demands of their occupation.     

运动训练对大鼠主动脉应力和NF-κB及c-fos表达的影响

目的：探讨不同强度运动训练对大鼠主动脉应力和NF-κB及c-fos表达的影响。方法：采用跑台训练方式,建立大鼠有氧运动和疲劳运动模型,运用免疫组织化学SABC法研究不同强度运动训练对大鼠主动脉VEC和VSMC中NF-κB及c-fos表达的影响。结果：胸主动脉血压的变化与对照组比较,有氧训练和疲劳训练均显著性升高（P〈0．05）,但有氧训练与疲劳训练之间差异不显著。与对照组比较,有氧训练大鼠VEC和VSMC中NF-κB和c-fos均显著性下调表达,胸主动脉张开角显著性升高（P〈0．05）,疲劳训练大鼠VEC和VSMC中NF-κB和c-fos均显著性上调表达（P〈0．05）。与有氧运动组比较,疲劳运动大鼠VEC和VSMC中NF-κB和c-fos表达与胸主动脉张开角升高均具有显著性差异（P〈0．05）。表明不同强度运动大鼠主动脉VEC中NF-κB和c-fos表达变化趋势不同,疲劳训练组表达的增加趋势更显著。结论：运动可引起大鼠主动脉VEC和VSMC NF-κB及c-fos表达的变化,且与运动强度关系密切。有氧训练引起的慢性剪切应力变化可使主动脉VEC和VSMC NF-κB加及c-fos显著性下调表达,与VEC和VSMC维持血管功能的稳态有关;疲劳训练可导致壁面摩擦剪切力、周向应力增加,过度的剪切力作用可引起主动脉VEC和VSMC NF-κB及c-fos显著性上调表达,血管张开角显著增加,血管发生非均匀生长,引起血管结构与功能的重塑。     

Effects of exercise training on plasma catecholamines and blood pressure in labile hypertensive subjects

Plasma catecholamine concentrations (norepinephrine, NE; epinephrine, E) were measured along with heart rate (HR) and blood pressure (BP) at rest in supine (20 min) and standing (10 min) positions and in response to cycle ergometer exercise (5 min; 60% estimated maximal aerobic power) in 12 hypertensive patients before and after 20 weeks of aerobic training on cycle ergometer (six males, one female) or by jogging (five males). In a control group of labile hypertensive patients (five males, two females), estimated maximal aerobic power as well as HR and BP at rest in the supine and standing positions and in response to exercise were not modified from the first to the second evaluation (43 +/- 4 vs 43 +/- 5 ml.kg-1.min-1). In comparison estimated maximal aerobic power significantly increased in both training groups (cycle: 38 +/- 4 to 43 +/- 4; jogging: 38 +/- 3 to 46 +/- 4 ml.kg-1.min-1). However HR and BP were not modified following training, except for small reductions in systolic (18.9 to 18 kPa: 142 to 135 mmHg) and diastolic pressures (13.3 to 12 kPa: 100 to 90 mmHg) (p less than 0.05) at standing rest in the cycle group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of training intensity distribution on aerobic fitness variables in elite soccer players: a case study

The aim of this article was to quantify the distribution of training intensities and its effect on aerobic fitness in professional elite soccer players. Fourteen professional soccer players were observed during the prechampionship training period (6 weeks). Treadmill running speed and heart rates (HRs) at 2 and 4 mmol · L(-1) blood-lactate concentrations were assessed pre and posttraining. Training intensities were categorized using 3 HR zones: low intensity (

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HR 4 mmol · L(-1)). Analysis of the 504 individual training sessions showed that 73 ± 2.5, 19 ± 2.8, and 8 ± 1.4% of the total training time was spent at low, moderate, and high intensity, respectively (p < 0.001). Speed at 2 and 4 mmol · L(-1) significantly improved posttraining (5 and 7%, respectively, p < 0.01). Training spent at high intensity was significantly related to relative speed improvements at 2 mmol · L(-1) (r = 0.84, p < 0.001;) and 4 mmol · L(-1) (r = 0.65, p = 0.001). Players spent almost two-thirds of their training time at low intensities. However, only the time spent at high intensity (>90% of maximal HR) was related to changes in aerobic fitness. These results support the usefulness of the quantification of aerobic training load using HR. Furthermore, it stresses the effectiveness of the high-intensity training in soccer.     

Suitability of soccer training drills for endurance training

Recent evidence suggests that certain soccer drills produce exercise intensities suitable for physical conditioning. However, it remains debatable whether soccer drills can provide a sufficiently unified exercise intensity among different players and on repetition of a drill, because movement patterns cannot be externally controlled during soccer drills. Good reliability and low variability of exercise intensity would enable all players to receive an appropriate training stimulus. The purpose of this study was to investigate intersubject variability and intrasubject reliability in exercise intensity during soccer drills. It was hypothesized that soccer drills that involve the highest exercise intensities would demonstrate the lowest intersubject variability and the highest intrasubject reliability. Heart rates of 23 professional soccer players were recorded during a range of soccer training drills. The drills consisted of 2 vs. 2 to 8 vs. 8 normal scoring games and 2 further possession games. Heart rate responses were examined for variability, reliability, and suitability for soccer endurance training. Coefficients of variation across players were less than 3% for all drills. Paired t-tests showed no significant differences in heart rate on repetition of the drills and 95% ratio limits of agreement were 1.8-3.8%. There were no significant correlations between exercise intensity and the statistical measures of variability and reliability. Several drills produced exercise intensities suitable for soccer endurance training with mean heart rate responses ranging from 87-91% HRmax. Soccer drills such as those used in the present study appear to be an adequate substitute for physical training without the ball and thus provide simultaneous skill and fitness training. The increase in training time spent developing technical ability and/or a reduction in total training time required may be useful for soccer teams.     

Exercise Training Prevents Regain of Visceral Fat for 1 Year Following Weight Loss

The purpose of this study was to determine what effect aerobic and resistance exercise training has on gain of visceral fat during the year following weight loss. After being randomly assigned to aerobic training, resistance training, or no exercise training, 45 European‐American (EA) and 52 African‐American (AA) women lost 12.3 ± 2.5 kg on a 800 kcal/day diet. Computed tomography was used to measure abdominal subcutaneous and visceral adipose tissue, whereas total fat and regional fat (leg, arm, and trunk) were measured by dual energy X‐ray absorptiometry after weight loss and 1 year following the weight loss. Because not all the subjects adhered to the 2 time/week 40 min/day exercise training during the 1‐year follow‐up, subjects were divided into five groups for analysis: aerobic adherers, aerobic nonadherers, resistance adherers, resistance nonadherers, and no exercise. No significant differences were observed between the aerobic training and resistance training adherers for any variable. However, the aerobic (3.1 kg) and resistance (3.9 kg) exercise adherers gained less weight than any of the other three groups (all >6.2 kg). In addition, the two exercise adherence groups did not significantly increase visceral fat (<0.8%) as compared with the 38% increase for the two nonadhering exercise groups and the 25% for the nonexercise group. In conclusion, as little as 80 min/week aerobic or resistance training had modest positive effects on preventing weight regain following a diet‐induced weight loss. More importantly, both aerobic and resistance training prevented regain of potentially harmful visceral fat.     

Strength cycle training: effects on muscular strength and aerobic conditioning

The strength cycle ergometer has been proposed as a method of simultaneously increasing aerobic conditioning and muscular strength, because of its unique capacity of disengaging the pedal crank, thus allowing for concurrent single-leg cycling. The purpose of this study was to assess the aerobic and muscular strength effects of strength cycle training (SCT), comparing it to similar standard cycle training. A total of 28 recreationally-trained adult subjects (9 men, 19 women) were paired for VO2peak and randomly assigned to either SCT or Monark cycle training (MCT). Subjects trained 3 days per week following a progressive interval protocol for 9 weeks under supervised conditions. Training intervals (5 minutes' duration) consisted of 3 minutes of standard cycling at an intensity of 60-85% of maximum heart rate (HRmax), and 2 minutes of either the disengaged cycling mode (SCT) or standard cycling plus 30 W (MCT). Subjects began training for a total of 25 minutes per session, progressing to 45 minutes per session by study's end. Prior to and following training, subjects were measured for VO2peak; submaximal VO2, heart rate (HR), RPE, power output, and knee and ankle isokinetic strength. Training resulted in significant (p < or = 0.05) increases in VO2peak (14.5%) and submaximal power output (11%), and significant reductions in submaximal VO2, HR, and RPE in both groups. Significant increases in bilateral isokinetic knee extension (4-6%) and left ankle plantar flexion (10.5%) were noted following training in both groups. No group differences were detected in any variable. Although the strength cycle effectively increased aerobic function and resulted in modest selected increases in lower-extremity muscular strength, these changes were not different from those seen using a similar standard cycling protocol.     

Endurance training reduces the magnitude of exercise-induced hyperammonemia in humans

The purpose of this study was to determine the influence of endurance-type exercise training on alterations of the ammonia content of blood in exercising humans. Seven females and four males trained 6 days/wk for 7 wk alternating days of continuous cycling (40 min) and interval running (five 5-min bouts). The NH3 content of blood was determined before and during cycle ergometer (CE) exercise (4 min) at power outputs (PO) of 119, 172, and 241 W pretraining and of 163, 230, and 271 W posttraining. These PO for each occasion represent relative work loads of approximately 65, 90, and 115% of peak CE maximum O2 uptake (PCE VO2), respectively. Training increased (P less than 0.05) PCE VO2 approximately 32% (2.72 +/- 0.25 to 3.56 +/- 0.29 l/min or 38.5 +/- 1.9 to 51.2 +/- 2.3 ml X kg-1 X min-1). Both pre- and posttraining the NH3 content of blood increased (P less than 0.05) with increasing intensity of exercise. Training did not influence the measure of these responses during exercise at the same relative intensity. During exercise at the same absolute PO, approximately 168 or 235 W, however, increases in blood NH3 were less (P less than 0.05) after training. The results indicate that the magnitude of increase in blood NH3 during exercise is determined by the energy requirement of the absolute work load, relative to an individual's aerobic power.     

Exercise training programs in Dutch cardiac rehabilitation centres

Purpose

To assess methods for determination of exercise intensity, and to investigate practice variation with respect to the contents, volume and intensity of exercise training programs in Dutch cardiac rehabilitation (CR) centres.

Methods

A paper questionnaire was sent to all Dutch CR centres, consisting of 85 questions for patients with an acute coronary syndrome (ACS) or after coronary revascularisation (Group 1) and for patients with chronic heart failure (CHF, Group 2).

Results

CR professionals from 45 centres completed the questionnaires (58 %). Symptom-limited exercise testing was used to determine exercise capacity in 76 % and 64 % of the CR centres in group 1 and group 2, respectively; in these centres, a percentage of the maximum heart rate was the most frequently used exercise parameter (65 % and 56 %, respectively). All CR centres applied aerobic training and the majority applied strength training (64 % in group 1 and 92 % in group 2, respectively). There was a considerable variation in training intensity for both aerobic and strength training, as well as in training volume (1–20 h and 1–18 h respectively).

Conclusion

Among Dutch CR centres, considerable variation exists in methods for determination of exercise intensity. In addition, there is no uniformity in training volume and intensity.     

The use of muscle near-infrared spectroscopy (NIRS) to assess the aerobic training loads of world-class rowers

The objectives of this study were (1) to characterize the changes in oxygenation derived from muscle near-infrared spectroscopy (NIRS) during aerobic constant-load exercise with intensities close to Maximal Lactate Steady-State (MLSS) and (2) to establish reference values in the world-class rowers, for such workload often included in rowing training programs. Eight senior world-class rowers performed an incremental progressive submaximal exercise test and a 30-minute test on a rowing ergometer. The power corresponding to intensive aerobic training (84±1% of the anaerobic threshold) was adopted as an exercise load in the 30-minute test. The NIRS device was fixed on the vastus lateralis muscle which was active during rowing to record muscle O₂ saturation (SmO₂) and total hemoglobin concentration (THb) at rest and during exercise. Statistically significant increments in blood lactate (LA) and heart rate (HR) were observed, with 1.18±0.61 mmol/l and 10±5 beats/min, respectively, in 30th minute compared to 10th minute in 30-minute test. SmO₂ decreased significantly by 2.9±1.4%, whereas THb did not change. The examinations may suggested the low diagnostic value of THb in constant-load exercise. In each subject, SmO₂ was gradually reduced during the intense aerobic exercise. During workload close to MLSS, the SmO₂ of the vastus lateralis ranged from 14.0±3.13 to 11.1±2.81% in 10 and 30 minutes respectively, with a reduction in muscle oxygenation (ΔSmO₂) exceeding 50%. The non-invasive nature of the NIRS measurement and the continuous monitoring of SmO₂ values are useful in the practice of monitoring training in terms of aerobic training loads.     

Improved estimation of total oxygen uptake in exercise by evaluation of aerobic fitness

The purpose of the present study was to contrive a new practical method for estimating total O2 uptake during exercise from total heart beats after individual evaluation of aerobic fitness levels. Twenty healthy male subjects participated in cycle ergometer tests, maximal O2 uptake (VO2max) tests and various simple tests including simple endurance tests. From the cycle ergometer results, the following formula for estimating total O2 uptake in exercise was determined: TVO2 (ml X kg-1) = SR125 X (45.8 X mean HR + 4268) X THB X 10(-4) where TVO2, THB, and mean HR are total O2 uptake, total heart beats, and mean heart rate (beats X min-1) in exercise, respectively, and SR125 is the slope of the regression line between accumulated heart beats and accumulated O2 uptake during exercise at 125 beats X min-1 of mean HR. SR125 had a significant correlation not only with VO2max but also with each score (X) in any simple endurance tests such as, for example, a step test for 2 min. In this case, accordingly, SR125 can be found as; SR125 = -0.00118X + 0.3478. These formulae indicate that the total O2 uptake of any exercising subject can be estimated from his total heart beats regardless of intensities of exercise when his aerobic fitness level is evaluated by the simple endurance test. The total O2 uptake estimated by our method was compared to that measured by the Douglas bag method, and the discrepancy between the two results was less than the errors of values estimated by traditional methods.     

Breathing during exercise in subjects with mild-to-moderate airflow obstruction: effects of physical training.

In this study we explored the effects of physical training on the response of the respiratory system to exercise. Eight subjects with irreversible mild-to-moderate airflow obstruction [forced expiratory volume in 1 s of 85 +/- 14 (SD) % of predicted and ratio of forced expiratory volume in 1 s to forced vital capacity of 68 +/- 5%] and six normal subjects with similar anthropometric characteristics underwent a 2-mo physical training period on a cycle ergometer three times a week for 31 min at an intensity of approximately 80% of maximum heart rate. At this work intensity, tidal expiratory flow exceeded maximal flow at control functional residual capacity [FRC; expiratory flow limitation (EFL)] in the obstructed but not in the normal subjects. An incremental maximum exercise test was performed on a cycle ergometer before and after training. Training improved exercise capacity in all subjects, as documented by a significant increase in maximum work rate in both groups (P < 0.001). In the obstructed subjects at the same level of ventilation at high workloads, FRC was greater after than before training, and this was associated with an increase in breathing frequency and a tendency to decrease tidal volume. In contrast, in the normal subjects at the same level of ventilation at high workloads, FRC was lower after than before training, so that tidal volume increased and breathing frequency decreased. These findings suggest that adaptation to breathing under EFL conditions does not occur during exercise in humans, in that obstructed subjects tend to increase FRC during exercise after experiencing EFL during a 2-mo strenuous physical training period.     

Day-to-day changes in oxygen uptake kinetics at the onset of exercise during strenuous endurance training.

The aim of this study was to assess the effect of strenuous endurance training on day-to-day changes in oxygen uptake (VO2) on-kinetics (time constant) at the onset of exercise. Four healthy men participated in strenuous training for 30 min.day-1, 6 days.week-1 for 3 weeks. The VO2 was measured breath-by-breath every day except Sunday at exercise intensities corresponding to the lactate threshold (LT) and the onset of blood lactate accumulation (OBLA) which were obtained before training. Furthermore, an incremental exercise test was performed to determine LT, OBLA and maximal oxygen uptake (VO2max) before and after the training period and every weekend. The 30-min heavy endurance training was performed on a cycle ergometer 5 days.week-1 for 3 weeks. Another six men served as the control group. After training, significant reductions of the VO2 time constant for exercise at the pretraining LT exercise intensity (P less than 0.05) and at OBLA exercise intensity (P less than 0.01) were observed, whereas the VO2 time constants in the control group did not change significantly. A high correlation between the decrease in the VO2 time constant and training day was observed in exercise at the pretraining LT exercise intensity (r = -0.76; P less than 0.001) as well as in the OBLA exercise intensity (r = -0.91; P less than 0.001). A significant reduction in the blood lactate concentration during submaximal exercise and in the heart rate on-kinetics was observed in the training group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Efficacy of two intervention approaches on functional walking capacity and balance in children with Duchene muscular dystrophy

Objectives:Children with Duchene muscular dystrophy have weak muscles, which may impair postural adjustments. These postural adjustments are required for gait and dynamic balance during the daily living activities. The aim was to compare between the effect of bicycle ergometer versus treadmill on functional walking capacity and balance in children with Duchenne muscular dystrophy.Methods:Thirty boys aged from 6 to 10 years old diagnosed as Duchene muscular dystrophy participated in this study. Children were assigned randomly into two groups (A&B). Children in group (A) underwent a designed program of physical therapy plus aerobic exercise training in form of bicycle ergometer while, group (B) received the same program as group (A) and aerobic exercise training by treadmill for one hour, at three times a week for three successive months. Functional walking capacity and balance were assessed before and after treatment by using the 6-minute walk test and Biodex balance system equipment respectively.Results:The post treatment results revealed significant difference in all measured variables (P<0.05) as compared with its pre-treatment results. Post-treatment values indicated that there was a significant difference in all measured variables in favor of group B.Conclusions:treadmill training as an aerobic exercise can improve walking capacity and balance more effectively than bicycle ergometer in children with Duchenne muscular dystrophy.