Biomedical subjects

Jon Ingulf Medbø

Publications and source records attributed to Jon Ingulf Medbø.

5 recordsLinked to original sources

PubMed2006

Physiological responses of firefighters and performance predictors during a simulated rescue of hospital patients.

There is incomplete information about how physically demanding rescue work may be. The aim therefore of this paper was to examine the physiological responses of firefighters during a simulated rescue of hospital patients and to relate the firefighters' performance to their endurance, strength and working technique. Fourteen part-time male firefighters with a maximal oxygen uptake (VO(2max)) of 4.4 +/- 0.3 l/min (mean +/- SD) served as subjects in this study. First, each firefighter ascended six floors (a 20.5 m vertical ascent) carrying tools, wearing protective clothing and a breathing apparatus, an extra mass of 37 kg. He thereafter 'rescued' six persons by dragging each person on a fire-sheet on a flat floor. The technique used was recorded and the O(2) uptake and the heart rate were measured continuously during the whole operation. The blood lactate concentration and the subjective rating of perceived exertion were measured during and just after the rescue. The VO(2max) and the muscle strength were measured in the laboratory. The whole operation was carried out in the course of 5-9 min. The operation was a virtual all-out effort and the peak blood lactate concentration was 13 +/- 3 mmol/l. The peak oxygen uptake was 3.7 +/- 0.5 l/min (84% of the VO(2max)) during the operation. Large and heavy firefighters carried out the task faster than smaller ones. The VO(2max) in absolute terms and the dragging technique used were both related to the rescue performance. Rescuing patients at a hospital was physically very demanding and the time needed to complete the task depended on the VO(2max) in absolute values and the working technique used. A minimum VO(2max) of 4 l/min for firefighters was recommended.

Adult↗

PubMed2006

Muscular performance after concentric and eccentric exercise in trained men.

PURPOSE: We studied previously resistance-trained men and compared the effects of concentric and eccentric training on performance and structural muscle parameters. METHODS: Seventeen trained individuals (age 26.9 +/- 3.4 yr) participated in 12 wk of either maximum concentric (N = 8) or eccentric (N = 9) resistance training of the elbow flexors. The functional performance was measured as the maximum concentric and eccentric strength and angular velocity at standard loads. Muscle cross-sectional area and cross-sectional area of single cells were used as measures of muscular hypertrophy. Fiber-type proportions were assessed by staining cells for myofibrillar ATPase. RESULTS: Both eccentric and concentric training increased concentric strength to a similar extent (14 vs 18%), whereas eccentric training led to greater increases in eccentric strength than concentric training did (26 vs 9%). The maximum angular velocity at all loads was enhanced equally in both training groups. The cross-sectional area of both the elbow flexors (+11%) and of the type I and type IIA fibers increased only after the eccentric training. In addition, the relative cross-sectional area occupied by the type II fibers increased from 64 to 73% after the eccentric training. There were only minor changes in the fiber-type proportions. CONCLUSION: The present data suggest that for resistance-trained men, increases in concentric strength and velocity performance after eccentric training are largely mediated by changes in fiber and muscle cross-sectional area. However, hypertrophy alone could not explain the increase in eccentric strength. Because the increases in strength and velocity performance after concentric training could not be ascribed to muscular adaptations alone, we suggest that they may be attributable to additional neural factors.

Adult↗

PubMed2005

Effect of intensive acupuncture on pain-related social and psychological variables for women with chronic neck and shoulder pain--an RCT with six month and three year follow up.

OBJECTIVES: This study examines whether intensive acupuncture treatment can improve several social and psychological variables for women with chronic pain in the neck and shoulders, and whether possible effects are long-lasting. The effects on pain have been reported elsewhere. METHODS: Twenty-four female office workers (47 +/- 9 years old, mean +/- SD) who had had neck and shoulder pain for 12 +/- 9 years, were randomly assigned to a test group or a control group. Acupuncture was applied 10 times during three to four weeks either at presumed acupuncture points for pain (test group) or at sham points (control group). In addition, acupressure was given to patients between treatments, at either real or sham points. Questionnaires for social and psychological variables were completed before each treatment, just after the course, and six months and three years later. RESULTS: The pain-related activity impairment at work was significantly less in the test group than the controls by the end of treatment (P < 0.04). Also there were significant differences between the groups for quality of sleep, anxiety, depression and satisfaction with life (P < 0.05). At six months and three years follow ups the acupuncture group showed further improvements in most variables and was again significantly different from the control group. CONCLUSION: Intensive acupuncture treatment may improve activity at work and several relevant social and psychological variables for women with chronic pain in the neck and shoulders. The effect may last for at least three years.

Acupuncture Analgesia↗

PubMed2004

Effect of acupuncture treatment on chronic neck and shoulder pain in sedentary female workers: a 6-month and 3-year follow-up study.

The study was carried out to examine whether acupuncture treatment can reduce chronic pain in the neck and shoulders and related headache, and also to examine whether possible effects are long-lasting. Therefore, 24 female office workers (47+/-9 years old, mean+/-SD) who had had neck and shoulder pain for 12+/-9 years were randomly assigned to a test group (TG) or a control group (CG). Acupuncture was applied 10 times during 3-4 weeks either at presumed anti-pain acupoints (TG) or at placebo-points (CG). A physician measured the pain threshold (PPT) in the neck and shoulder regions with algometry before the first treatment, and after the last one and six months after the treatments. Questionnaires on muscle pain and headache were answered at the same occasions and again 3 years after the last treatment. The intensity and frequency of pain fell more for TG than for CG (Pb < or = 0.04) during the treatment period. Three years after the treatments TG still reported less pain than before the treatments (Pw < 0.001) contrary to what CG did (Pb < 0.04) The degree of headache fell during the treatment period for both groups, but more for TG than for CG (Pb=0.02) Three years after the treatments the effect still lasted for TG (Pw < 0.01) while the degree of headache for CG was back to the pre-treatment level (Pb < 0.001) PPT of some muscles rose during the treatments for TG and remained higher 6 months after the treatments (Pw < 0.05) which contrasts the situation for CG. Adequate acupuncture treatment may reduce chronic pain in the neck and shoulders and related headache. The effect lasted for 3 years.

Acupuncture Analgesia↗

PubMed2003

Energy cost of free technique and classical cross-country skiing at racing speeds.

PURPOSE: First, to measure the O(2) uptake ([OV0312]O(2)) and the blood lactate concentration during cross-country skiing at competition speed. Second, to compare these entities for the free technique and the classical technique. Further, to establish the subjects' [OV0312]O(2max) and the [OV0312]O(2) corresponding to the onset of blood lactate accumulation (OBLA, 4 mmol.L-1) during skiing, and finally to relate these entities to those of treadmill running. METHODS: Five high-level female junior cross-country skiers with a mean [OV0312]O(2max) of 63 mL.kg-1.min-1 served as subjects in five tests: examination of the [OV0312]O(2max) and the [OV0312]O(2) corresponding to the OBLA during up-hill cross-country skiing (both styles), inclined treadmill running, and a 6-km simulated cross-country ski race (both styles). RESULTS: The [OV0312]O(2max) obtained during up-hill cross-country skiing did not differ from that during treadmill running, nor did it differ between the two skiing styles. The peak heart rate was significantly lower during uphill cross-country skiing than during treadmill running. During the simulated competitions, the [OV0312]O(2) averaged 84% of the [OV0312]O(2max) or 95% of the [OV0312]O(2) at the OBLA found for uphill skiing. CONCLUSION: High-level female junior cross-country skiers are unable to ski at intensities close to their [OV0312]O(2max) or maintain an average intensity above that corresponding to their OBLA even during races lasting less than 25 min. Thus, training at intensities around the OBLA may be particularly relevant for cross-country skiers.

Adolescent↗