Biomedical subjects

Jesper Strøyer

Publications and source records attributed to Jesper Strøyer.

3 recordsLinked to original sources

PubMed2004

The role of back muscle endurance, maximum force, balance and trunk rotation control regarding lifting capacity.

Evaluation of lifting capacity is widely used as a reliable instrument in order to evaluate maximal and safe lifting capacity. This is of importance in regard to planning rehabilitation programs and determining working ability. The aim of this study was to investigate the influence of basic functions on the lifting capacity measured by the progressive isoinertial lifting evaluation (PILE) and the functional capacity evaluation (FCE) tests in a lower (floor to waist) and an upper (waist to shoulder) setting and compare the two test constructs. Seventy-four female subjects without acute low back pain underwent an examination of their lifting capacities and the following basic functions: (1) strength and endurance of trunk muscles, (2) cardiovascular endurance, (3) trunk mobility and (4) coordination ability. A linear regression model was used to predict lifting capacity by means of the above-mentioned basic functions, where the F statistics of the variables had to be significant at the 0.05 level to remain in the model. Maximal force in flexion showed significant influence on the lifting capacity in both the PILE and the FCE in the lower, as well as in the upper, lifting task. Furthermore, there was a significant influence of cardiovascular endurance on the lower PILE and also of endurance in trunk flexion on the lower FCE. Additional inclusion of individual factors (age, height, weight, body mass index) into the regression model showed a highly significant association between body height and all lifting tasks. The r (2) of the original model used was 0.19/0.18 in the lower/upper FCE and 0.35/0.26 in the lower/upper PILE. The model r (2) increased after inclusion of these individual factors to between 0.3 and 0.4. The fact that only a limited part of the variance in the lifting capacities can be explained by the basic functions analyzed in this study confirms the assumption that factors not related to the basic functions studied, such as lifting technique and motor control, may have a strong influence on lifting capacity. These results give evidence to suggest the inclusion of an evaluation of lifting capacity in clinical practice. Furthermore, they raise questions about the predictive value of strength and endurance tests in regard to lifting capacity and work ability.

Back↗

PubMed2004

Physiological profile and activity pattern of young soccer players during match play.

PURPOSE: The purpose of this study was to examine aerobic demands and activity patterns during match play in young soccer players with respect to competition level, age, and biological maturity. METHODS: Ten nonelite players (NbP) and nine elite players (EbP) in their early puberty (12 yr), and seven elite players (EeP) in their late puberty (14 yr) were studied. Heart rate (HR) and activity pattern were recorded during match play, whereas corresponding .VO(2) and HR values were obtained during submaximal and maximal treadmill tests in the laboratory. The maturity status was assessed from testicular volume. RESULTS: No difference in .VO(2max) was observed between the nonelite and the elite players in the beginning of puberty (58.7 +/- 5.3 vs 58.6 +/- 5.0 mL O(2).min-1.kg(-1)), whereas the elite players in the end of puberty were significantly more fit (63.7 +/- 8.5 mL O(2).min(-1).kg(-1)). During match play, a higher HR was recorded in the elite players in the beginning of puberty than their nonelite counterparts, whereas the two elite groups showed the same HR responses (HR 1st half/2nd half-NbP: 162/157; EbP: 177/174; EeP: 178/173). The elite players in the end of puberty thus performed a higher absolute and relative .VO(2) (.VO(2).min(-1) and mL O(2).min(-1).kg(-1)) compared with the nonelite players during both halves, corresponding to more time spent in standing/walking in the nonelite group. The elite players in the end of puberty showed higher absolute .V(O2) values during match play than the young elite players but identical relative aerobic loads. It seems that the midfield/attack group had the highest absolute .VO(2max) and was performing at the highest HR during the matches. CONCLUSION: The present study shows that young soccer players are highly specialized both according to playing level and position on the field.

Adolescent↗

PubMed2004

Computer users' risk factors for developing shoulder, elbow and back symptoms.

OBJECTIVES: This prospective study concentrated on determining factors of computer work that predict musculoskeletal symptoms in the shoulder, elbow, and low-back regions. METHODS: A questionnaire on ergonomics, work pauses, work techniques, and psychosocial and work factors was delivered to 5033 office workers at baseline in early 1999 (response rate 69%) and to 3361 respondents at the time of the follow-up in late 2000 (response rate 77%). An increased frequency or intensity of symptoms was the outcome variable, including only nonsymptomatic respondents from the baseline questionnaire (symptom frequency below 8 days within the last 12 months or intensity score below 4 within the last 3 months). RESULTS: In the follow-up, 10%, 18%, and 23% had symptoms more often in the elbow, shoulder, and low back, respectively, and 14%, 20%, and 22% had more intense symptoms. Women were more likely to be afflicted than men in all regions. In the full-fit multivariate logistic regression analysis, little influence on the timing of a rest pause and being disturbed by glare or reflection were significant predictors of shoulder symptoms, screen below eye height was a significant predictor for elbow symptoms, and previous symptoms was a significant predictor for symptoms in all regions. Computer worktime and psychosocial dimensions were not significant predictors. CONCLUSIONS: Influence on work pauses, reduction of glare or reflection, and screen height are important factors in the design of future computer workstations. Since previous symptoms was a significant predictor of recurrent symptoms in all three regions under study, it can be concluded that musculoskeletal symptoms are persistent.

Adult↗