Physical exercise for work- related musculoskeletal disorders overview of the last 10 years research in Denmark

Transcription

1 Physical exercise for work- related musculoskeletal disorders overview of the last 10 years research in Denmark Lars L. Andersen, Professor National Research Centre for the Working Environment, Denmark

2 Causes of sickness absence and disability pension 27 countries in Europe Musculoskeletal Disorders 50% Other causes 50% Bevan 2009

3 Prevalence of pain Denmark 25% 11% 29% Andersen LL 2011, Occ Env Med 12%

4 Office work and neck-shoulder pain

5 Sites of muscle tenderness 200 computer workers with neck-shoulder pain 75% 12% 75% 75% 63% Clinical examination Andersen LL 2011, BMC MSD

6 Vision 2. Precision 3. Poor posture 4. Stress Too much work and stress, too little rest Accumulated fatigue Pain Chronic pain, sensitization Larsson B 2007, BPRCR Andersen LL 2011, BMC MSD

7 Work load - A good working environment - Ensure good organization of the work - Use assistive devices during heavy lifting - Break up sedentary behavior Physical Fitness - Physical exercise at work Health at work

8 Around year 2005 Strength training is bad for overactive, tight and painful neck and shoulder muscles

9 10 years later Strength training is good for overactive, tight and painful neck and shoulder muscles

10 1. Which type of exercise works best? 3. How flexible can planning of the exercise be? 2. How can exercise be implemented and sustained on a larger scale? 4. How little exercise is enough? 5. Are the results generalizable across job groups?

11 At the workplace 3 x 20 min/week 10 weeks Progressive overload Andersen LL 2008, Arthr Rheum

12 Cycling improves pain here and now, but the effect is gone after 2 hours Andersen LL 2008, Arthr Rheum

13 Pain intensity RCT 70 WORST PAIN Only strength training lead to long-lasting pain reduction WORST PAIN Worst Pain (mm) Worst Pain (mm) weeks 5 10 training weeks no-training Session Session * wks post-intervention Weeks wks post-intervention Weeks Control Cycling Strength training at the workplace Andersen LL 2008, Arthr Rheum

14 Pain (0-100 mm) over Above åryrs under Below 45 yrs år Training session Strength training works regardsless of age Andersen LL (unpublished)

15 Oldest employee (58 year) Andersen LL (unpublished)

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17 Satellite cells new muscle cell nuclei improved potential for muscle recovery after work 164% Before 65% After 10 weeks Control Cycling Strength training Mackey AL 2011, J Physiol

18 nnos NO: involved in regulation of blood flow to muscles Jensen L 2015 Biomed Res Int

19 Strength training effectively reduces neckshoulder pain in the long-term It is never too late to begin Positive adaptations at muscle cellular level

20 1. Which type of exercise works best? 3. How flexible can planning of the exercise be? 2. How can exercise be implemented and sustained on a larger scale? 4. How little exercise is enough? 5. Are the results generalizable across job groups?

21 Zebis MK 2011, BMC MSD Andersen LL 2012, BMJ Open RCT Strength training at the workplace 500 lab technicians Leaders, workers, work env. organization Regular training: 87% Neck pain: 38% 3 x 20 min/uge

22 Long-lasting effects even after 3 years Mortensen P 2014, Biomed Res Int

23 Strength training at the workplace can have long-lasting benefits Context is important

24 1. Which type of exercise works best? 3. How flexible can planning of the exercise be? 2. How can exercise be implemented and sustained on a larger scale? 4. How little exercise is enough? 5. Are the results generalizable across job groups?

25 RCT VIMS - II 600 office workers 1 hour per week 1 hour 3 x 20 min 9 x 7 min OR Andersen CH 2012, BJSM, Gram B 2014, BMRI

26 Ændring i oplevet smerte Andersen CH 2012, BJSM Gram B 2014, Biomed Res Int RCT Neck-shoulder pain 600 office workers 1 hour per week 0 1WS 3WS 9WS 3MS CON % % -48 % -47 % %

27 1 hour of strength training per week can be distributed in different ways and still be effective Instruction during the inital week appears to be enough

28 1. Which type of exercise works best? 3. How flexible can planning of the exercise be? 2. How can exercise be implemented and sustained on a larger scale? 4. How little exercise is enough? 5. Are the results generalizable across job groups?

29 RCT 2-min 12-min Control N = 198 Frequent neck/shoulder pain Andersen et al 2011, Pain

30 Avr 3 times per week 2-min 12-min Andersen LL 2014, Int J Rheum

31 vę ret vę rst indenfor den seneste uge Neck-shoulder pain min 12 min Control Smerte intensitet (0-10) * Uge Andersen LL 2011, Pain

32 Andersen LL 2012, Pain Physician

33 Pressure Pain Threshold Andersen LL 2012, Pain Physician

34 Central adaptation of pain perception Andersen LL 2012, Pain Physician

35 Muscle activity (EMG) measured for 7 hours during the working day EMG gaps = micro-breaks of muscle activity Lidegaard M 2014, BMRI

36 Gaps/min Muscle micro-breaks during the workday EMG gaps * 2-min (n=15) Kontrol (n=15) Baseline 10-week followup Lidegaard M 2014 Biomed Res Int

37 2 minutes of strength training per day reduce neck-shoulder pain Central adaptations of pain perception Muscles better at relaxing during the workday

38 Most people prefer variation of exercises Andersen LL 2014, Int J Rheum

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40 Which type of exercise works best? How flexible can planning of the exercise be? How can exercise be implemented and sustained on a larger scale? How little exercise is enough? Are the results generalizable across job groups?

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42 Pain reduction 39% Pain reduction 37%

43 1. Which type of exercise works best? 3. How flexible can planning of the exercise be? 2. How can exercise be implemented and sustained on a larger scale? 4. How little exercise is enough? 2-min 5. Are the results generalizable across job groups?

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