Effect of physical exercise interventions on musculoskeletal pain in all body regions among office workers: A one-year randomized controlled trial

Strength training increases the size of the satellite cell pool in type I and II fibres of chronically painful trapezius muscle in females

While strength training has been shown to be effective in mediating hypertrophy and reducing pain in trapezius myalgia, responses at the cellular level have not previously been studied. This study investigated the potential of strength training targeting the affected muscles (SST, n = 18) and general fitness training (GFT, n = 16) to augment the satellite cell (SC) and macrophage pools in the trapezius muscles of women diagnosed with trapezius myalgia. A group receiving general health information (REF, n = 8) served as a control. Muscle biopsies were collected from the trapezius muscles of the 42 women (age 44 ± 8 years; mean ± SD) before and after the 10 week intervention period and were analysed by immunohistochemistry for SCs, macrophages and myonuclei. The SC content of type I and II fibres was observed to increase significantly from baseline by 65% and 164%, respectively, with SST (P < 0.0001), together with a significant correlation between the baseline number of SCs and the extent of hypertrophy (r = -0.669, P = 0.005). SST also resulted in a 74% enhancement of the trapezius macrophage content (P < 0.01), accompanied by evidence for the presence of an increased number of actively dividing cells (Ki67(+)) post-SST (P < 0.001). GFT resulted in a significant 23% increase in the SC content of type II fibres, when expressed relative to myonuclear number only (P < 0.05). No changes in the number of myonuclei per fibre or myonuclear domain were detected in any group. These findings provide strong support at the cellular level for the potential of SST to induce a strong myogenic response in this population.

Diet, physical exercise and cognitive behavioral training as a combined workplace based intervention to reduce body weight and increase physical capacity in health care workers - a randomized controlled trial

BACKGROUND

Health care workers comprise a high-risk workgroup with respect to deterioration and early retirement. There is high prevalence of obesity and many of the workers are overweight. Together, these factors play a significant role in the health-related problems within this sector. The present study evaluates the effects of the first 3-months of a cluster randomized controlled lifestyle intervention among health care workers. The intervention addresses body weight, general health variables, physical capacity and musculoskeletal pain.

METHODS

98 female, overweight health care workers were cluster-randomized to an intervention group or a reference group. The intervention consisted of an individually dietary plan with an energy deficit of 1200 kcal/day (15 min/hour), strengthening exercises (15 min/hour) and cognitive behavioral training (30 min/hour) during working hours 1 hour/week. Leisure time aerobic fitness was planned for 2 hour/week. The reference group was offered monthly oral presentations. Body weight, BMI, body fat percentage (bioimpedance), waist circumference, blood pressure, musculoskeletal pain, maximal oxygen uptake (maximal bicycle test), and isometric maximal muscle strength of 3 body regions were measured before and after the intervention period.

RESULTS

In an intention-to-treat analysis from pre to post tests, the intervention group significantly reduced body weight with 3.6 kg (p < 0.001), BMI from 30.5 to 29.2 (p < 0.001), body fat percentage from 40.9 to 39.3 (p < 0.001), waist circumference from 99.7 to 95.5 cm (p < 0.001) and blood pressure from 134/85 to 127/80 mmHg (p < 0.001), with significant difference between the intervention and control group (p < 0.001) on all measures. No effect of intervention was found in musculoskeletal pain, maximal oxygen uptake and muscle strength, but on aerobic fitness.

CONCLUSION

The significantly reduced body weight, body fat, waist circumference and blood pressure as well as increased aerobic fitness in the intervention group show the great potential of workplace health promotion among this high-risk workgroup. Long-term effects of the intervention remain to be investigated.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01015716.

Are low back pain and low physical capacity risk indicators for dropout among recently qualified eldercare workers? A follow-up study

BACKGROUND

A high job turnover and dropout among eldercare workers has led to a significant shortage of qualified manpower in the Danish eldercare sector.

OBJECTIVES

The predictive effect of some non-work-related causes for leaving the eldercare sector 2 years after qualification, physical capacity, duration, and severity of previous low back pain, was investigated.

DESIGN AND SETTING

A 2-year prospective cohort study of all the Danish eldercare workers, who finished their education during 2004 (n = 6347). Questionnaire data from 2004 were followed up by register data on attachment to labour market, educational status, and association to trade from Statistics Denmark in 2006.

METHODS

Data on physical capacity, duration, and severity of low back pain the last 12 months among the female participants were analysed by multinomial logistic regression to estimate odds-ratios for being either in the eldercare sector, in other health- and welfare sectors, in all other sectors, under education, or outside labour market, 2 years after qualification.

RESULTS

Disability due to and duration of low back pain were significant predictors for dropout from the eldercare sector 2 years after qualification. Low physical capacity was not. Data on duration of low back pain suggest a trend towards a dose-response relationship: The longer the duration of low back pain, the higher odds for dropout.

CONCLUSIONS

Low back pain and disability due to low back pain during the last year of education were independent predictors for dropout from the eldercare sector 2 years after qualification. However, low self-rated physical capacity did not predict job dropout or turnover.