Effects of external light loading in power-type strength training on muscle power of the lower extremities in middle-aged subjects.

The purpose of this study was to evaluate and compare the effects of training either with a light load or without any load in a 16-week power-type strength training intervention in sedentary middle-aged subjects. A total of 85 subjects participated in the study. In a supervised 22-week training intervention, including 16 weeks of power-type strength training, 42 subjects (Light Load group=LL group) trained with a 1.1 kg weight on each ankle and 43 subjects (No Load group=NOL group) trained without any external load. Subjects were comparable concerning their training attendance, and anthropometric and physiological characteristics. Training effects were evaluated by measuring Vertical Squat Jump (VSJ), 20-metre Running Time (20 mRT), Maximal Anaerobic Cycling Power of leg muscles (MACP), and Maximal Oxygen Uptake (V.O (2 max)) before and after the intervention. The LL group improved VSJ and MACP significantly (p<0.05), compared with the NOL group. No difference between the groups was observed in 20 mRT or in V.O (2 max). To conclude, the external loads of 2.2 kg, in total, increased the efficiency of power-type strength training in vertical jumps and in anaerobic power in leg muscles, but not in sprint running.

Effects of a 6-month exercise program on patients with multiple sclerosis: a randomized study.

OBJECTIVE: To improve walking and other aspects of physical function with a progressive 6-month exercise program in patients with multiple sclerosis (MS). METHODS: MS patients with mild to moderate disability (Expanded Disability Status Scale scores 1.0 to 5.5) were randomly assigned to an exercise or control group. The intervention consisted of strength and aerobic training initiated during 3-week inpatient rehabilitation and continued for 23 weeks at home. The groups were evaluated at baseline and at 6 months. The primary outcome was walking speed, measured by 7.62 m and 500 m walk tests. Secondary outcomes included lower extremity strength, upper extremity endurance and dexterity, peak oxygen uptake, and static balance. An intention-to-treat analysis was used. RESULTS: Ninety-one (96%) of the 95 patients entering the study completed it. Change between groups was significant in the 7.62 m (p = 0.04) and 500 m walk tests (p = 0.01). In the 7.62 m walk test, 22% of the exercising patients showed clinically meaningful improvements. The exercise group also showed increased upper extremity endurance as compared to controls. No other noteworthy exercise-induced changes were observed. Exercise adherence varied considerably among the exercisers. CONCLUSIONS: Walking speed improved in this randomized study. The results confirm that exercise is safe for multiple sclerosis patients and should be recommended for those with mild to moderate disability.

Exercise capacity, disability and leisure physical activity of subjects with multiple sclerosis.

The purpose of the present study was to examine exercise capacity and its relationship to neurological disability as measured using the Expanded Disability Status Scale (EDSS) and to leisure physical activity in subjects with multiple sclerosis (MS). Thirty-four men and 61 women (mean age 44 +/- 6.7 years, mean disease duration 5.7 +/- 6.4 years) with mild to moderate disability (EDSS range 1.0-5.5) participated. They underwent an incremental exercise test on a leg cycling ergometer. Leisure physical activity was measured using a questionnaire. Peak oxygen uptake (VO2peak) in men was 27.0 +/- 5.2 mL/kg/min, and in women 21.7 +/- 5.5 mL/kg/min. The disability correlated inversely with the VO2peak both in men (r = - 0.50, P = 0.004) and in women (r = - 0.25, P = 0.05). No correlation between disease duration and VO2peak was found. In a multivariate regression analysis, neurological disability was confirmed as a predictor of VO2peak. No evidence of a relationship between leisure physical activity and VO2peak was found. A main finding was that disability and exercise capacity are inter-related, even in subjects who are not severely handicapped (84% had an EDSS of < 4.0). The level of disability should be taken into account in the planning of aerobic exercise programs for fully ambulatory MS subjects.

Feasibility of power-type strength training for middle aged men and women: self perception, musculoskeletal symptoms, and injury rates.

OBJECTIVES: To examine the feasibility of a power-type strength training programme for middle aged men and women, the impact of the training programme on perceived health and fitness and on knee and low back symptoms, and the rate of exercise induced injuries. METHODS: A total of 154 voluntary, healthy, sedentary men and women participated in a training programme lasting about four months. The explosive force of leg extensor muscles was measured by means of standing long jumps and vertical squat jumps. Perceived health, perceived fitness, and low back and knee symptoms were assessed before and after the intervention by using a questionnaire. Musculoskeletal disorders and exercise induced injuries were reported during the training programme. RESULTS: Perceived fitness improved in both men (p<0.01) and women (p<0.0001), but perceived health only in women (p<0.01). Men with increased explosive force in squat jumping also showed better perceived health (p<0.05), and women with increased explosive force in standing long jump showed better perceived fitness (p<0.05). Exercising men who had increased knee symptoms had significantly higher body mass index than the other exercising men (p<0.05). The exercise induced injury rate was 19% in men and 6% in women. CONCLUSIONS: Successful completion of the exercise programme, together with the increased physical activity and relatively low injury rate, may have contributed to the participants finding the exercise programme positive and stimulating and believing that their health and fitness had improved. The low rate of musculoskeletal injury suggests that this type of supervised exercise programme is feasible for untrained middle aged people.

Dynamic balance in former elite male athletes and in community control subjects.

Dynamic balance was studied in 105 former elite athletes (aged 45-68) and in 966 community control subjects (aged 27-67). Subjects walked barefoot along a 5-m-long test track, stepping only on two pads which they alternately put down in front of them and picked up from behind while standing on one foot. A better test result (short completion time) was associated with lower body mass index (in both groups), with jumping height and physical activity during the previous year (in former athletes), and with younger age, better general health, and better perceived physical fitness (in control subjects). Test results in former athletes were, on average, comparable to those of 24-30 years younger community control subjects.

Isoresistive dynamometer measurement of trunk muscle velocity at different angular phases of flexion and extension.

Isoresistive trunk muscle dynamometer is a potentially useful piece of equipment in evaluation of trunk muscle velocity, but to date, studies analysing the possibilities and limitations of such measurements are scarce. The aim of this study was to analyse the trunk muscle velocity in repetitive flexion and extension movements at three different angular phases, using an isoresistive trunk muscle dynamometer, and to assess the reliability of the measurements. The study population consisted of 120 healthy, sedentary men and women who volunteered for the study. The measurements were carried out before and after a 22-week training intervention programme. The results show that the peak velocities of the phases between 15 and 35 degrees in flexion and 20-0 degrees in extension (i.e. the second phases) correlated highly (r=0.99 in flexion and in extension) with the peak velocity of the whole movement ranging from -5 to 55 degrees in flexion and 40 to -20 degrees in extension. Correlations were high, both before and after the intervention. The LISREL model analysis showed high reliability of measurement for the second angular phases (in flexion and extension). According to the model, the correlation between the first and second measurement (with a 22-week training intervention in between) was 0.78 in flexion and 0.81 in extension. In conclusion, the angular phases from 15 to 35 degrees in flexion and from 20 to 0 degrees in extension represent the peak velocity of the whole movement. Negative residual correlations between the first and last angular phases in the LISREL model reflect the way of performing the movement: the faster the start the slower the end, and vice versa.

Associations of isometric and isoinertial trunk muscle strength measurements and lumbar paraspinal muscle cross-sectional areas.

The relationships of dynamic and static trunk muscle strength measurements and muscle geometry are studied. Physiologically, isometric muscle strength is directly related to muscle cross-sectional area. We measured isometric and isoinertial trunk muscle strength of 111 former elite male athletes, aged 45-68, by Isostation B-200. Paraspinal muscle cross-sectional areas were measured from axial magnetic resonance images at the L3-L4 level. Isometric and isoinertial torques were closely related, but angular velocities were not predicted by isometric maximal torque. The area of the psoas muscles correlated with isometric maximal flexion, as well as with isoinertial maximal torque. angular velocity, and power in flexion (r = 0.24-0.27). The area of the extensor group correlated with isometric maximal extension and with isoinertial maximal torque and power in extension (r = 0.24-0.25). We conclude that dynamic and static strength measurements are closely related, with angular velocity giving additional information on muscle function. Paraspinal muscle cross-sectional area is one determinant of isometric and isoinertial trunk muscle strength.

Intensive physical and psychosocial training program for patients with chronic low back pain. A controlled clinical trial.

STUDY DESIGN: The authors conducted a controlled clinical trial with 1-year follow-up to define the effectiveness of an intensive physical and psychosocial training program on patients with low back pain. SUMMARY OF BACKGROUND DATA: The intervention group included 152 patients (mean age 40.5 yr, Million index 45.1/100), and the reference group included 141 patients (mean age 40.4 yr, Million-index 44.5/100). METHODS: The progressive intervention program consisted of intensive physical training and psychosocial activation. The outcomes were physical and psychosocial measures, the pain and disability index (Million), sick leaves, and occupational handicap. RESULTS: The intervention was more efficient with respect to physical measures and pain and disability index. There were only mild or no differences in changes between the study groups in psychologic variables, sick leaves, or retirement. CONCLUSIONS: The intervention program could improve physical disability, but to improve occupational handicap, activities of the whole society (social legislation, labor market policy) are needed.

Measurement of low back mobility, isometric strength and isoinertial performance with isostation B-200 triaxial dynamometer: reproducibility of measurement and development of functional indices.

The reproducibility of measurements with the triaxial lumbar dynamometer Isostation B-200 was measured in 61 volunteers with or without low back problems. Both for the intra- and interrater measurements the reproducibility was good (r = 0.76-0.89) for lateral flexions and almost as good (r = 0.76-0.87) for the sum of all ranges of motion (SROM). The corresponding reproducibilities were excellent (r = 0.82-0.99) for the isometric strength and good (r = 0.60-0.90) for isoinertial flexion-extension repetition test parameters in the main (primary axis) direction. A number of parameters were combined into three functional indices: the reproducibility for "power" and "work" index was good (r = 0.76-0.94) in both intra- and interrater conditions, whereas for "movement" index it was somewhat weaker (r = 0.53-0.87). It is concluded that parameters: lateral flexions, SROM, isometric strength, and functional indices (power and work) are reproducible enough to use in further studies.

Clinical findings as outcome predictors in rehabilitation of patients with sciatica.

In rehabilitation of patients with sciatica, factors prognostic of long-term outcome could prove beneficial in interventions and in evaluating progress toward fitness or capacity for work. In this study results of physical examinations, carried out one year after hospital treatment for suspected lumbar intervertebral disc herniation, were related to outcome after five-years, as assessed by the categorization of occupational handicap of the International Classification of Impairments, Disabilities and Handicaps (ICIDH). The sample consisted of 276 patients admitted to hospital in the years 1980-1982. Based on established clinical indications 179 patients underwent lumbar disc surgery and the remaining 97 received further conservative treatment. One year after hospitalization a physician and physiotherapist examined the patients at the Rehabilitation Research Centre (RRC) of the Social Insurance Institution in Finland. In 1986 the patients returned to the RRC for further evaluation of their occupational handicap at that time. Stepwise logistic regression analysis showed that sensory deficits of legs, tenderness in lumbar extension, decreased repetitive trunk flexion performance (sit-up test), decreased lumbar lordosis and tightness of hamstrings were indicative of a poor outcome in the operated group. For the non-operated patients no statistically acceptable regression analysis model could be established.

Marital satisfaction and distress in chronic low-back pain patients and their spouses.

This study examined the relation between marital satisfaction, psychological distress, self-reported pain, disability, and clinical findings in 63 chronic low-back pain (CLBP) patients from primary health care centers. The relation between marital satisfaction and psychological distress in their spouses was also studied. Marital dissatisfaction in female CLBP patients was significantly associated with psychological distress, as well as with patient self-reported pain and disability. Marital dissatisfaction in their male spouses was also strongly related to psychological distress. In male CLBP patient couples, marital dissatisfaction and psychological distress were much less significantly related. This gender difference should be taken into account in the treatment of CLBP couples.

Occupational class, physical workload, and musculoskeletal morbidity in the engineering industry.

In 1973, 502 employees in three metal industry plants, stratified by age, sex, and occupational class, were examined for physical workload by interview and observation at the workplace and for musculoskeletal disorders by questionnaire, interview, and clinical examination. Five years later, 88% of the sample were re-examined for their musculoskeletal status. The work of the blue collar groups was heavier as measured by indices of physical work load based on the observation and interview (physical strain, physical load, static phases, and stereotypy). Rheumatic symptoms, clinical findings in the musculoskeletal system, and chronic musculoskeletal diseases were more frequent in both female and male blue collar workers than in the respective white collar groups on the first occasion and the increase in morbidity during follow up was higher in the blue collar groups. At an individual level within the blue collar class, however, associations between indices of physical workload and musculoskeletal morbidity were weak or non-existent. The associations were weakened by selective movement of people with musculoskeletal disorders from heavy jobs to premature retirement or to lighter jobs. Physical strain and physical load were negatively associated with the incidence of long term musculoskeletal disorders in the female blue collar group.

Leisure time physical activities and the results of surgery of lumbar disc herniation.

The aim of this study was to elucidate the consequences of leisure time physical activities on the one-year results of surgery of lumbar intervertebral disc herniation. Pre- and postoperative leisure time physical activities and severity of occupation handicap were analyzed from 212 patients. Only to a certain degree the findings support the claim that a high preoperative level of physical activities during leisure time is linked with good postoperative results.

Performance capacity of trunk muscles in ankylosing spondylitis.

The comparative results of four tests (a dynamometer, a single and a repetitive dynamic and a static test) to determine the performance capacity of trunk muscles in ankylosing spondylitis are reported. Seventeen men and four women, aged 31 to 35 yrs, were examined. Trunk muscle performance was compared with the flexion mobility of the spine and ESR. The best correlation between muscle capacity of trunk extensors and spinal mobility was seen in the static trunk extensor test. The best correlation between muscle capacity of trunk flexors and spinal mobility was seen in the single dynamic test. Because the comprehensive exercise therapy including muscle strengthening is supported by our results and there is no generally recommended test for evaluating the performance capacity of trunk muscles, it seems reasonable to develop such tests of trunk muscles for clinical assessment of ankylosing spondylitis. Clinical trials to ensure the positive effect of well trained trunk muscles in ankylosing spondylitis are still lacking.