| 51. |
- Persson, Roger, et al.
(författare)
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Physiological and psychological reactions to work in men and women with identical job tasks
- 2009
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6327 .- 1439-6319. ; 105:4, s. 595-606
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Tidskriftsartikel (refereegranskat)abstract
- Differences in physiological functioning in the hypothalamus-pituitary-adrenal cortex axis and the autonomic nervous system have been suggested to contribute to many of the health differences that may be observed between men and women as well as being relevant for the development of musculoskeletal pain. To clarify whether men and women with identical work tasks reacted differently when doing work known to induce musculoskeletal pain, ratings and physiological measurements were obtained at work start (15:30) and at the end of the workshift (22:30) on 17 men and 20 women. Men showed a larger decrease in perceived energy levels during the workshift but there were no differences between men and women as regards cortisol, adrenaline, noradrenaline, heart-rate activation, perceived stress, pain and physical exertion. In conclusion, differential physiological activation during the workshift seem to be an unlikely mechanism for explaining gender differences in pain associated with exposure to awkward and repetitive movements.
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| 52. |
- Piedrahita, Hugo, et al.
(författare)
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Effect of local leg cooling on upper limb trajectories and muscle function and whole body dynamic balance
- 2009
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 105:3, s. 429-438
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Tidskriftsartikel (refereegranskat)abstract
- This study was designed to find out if local leg cooling affects muscle function and trajectories of the upper limb during repetitive light work as well as capability to maintain dynamic balance. Nine healthy female subjects performed repetitive lifting task with right hand for 60 min while standing in front of a table with six target angles (30°-220°) and with the legs inside a container with 15°C cold water (Cold condition, C) or without water (Normal condition, N). Muscle temperature of the medial aspect of the gastrocnemius, rectal, and skin temperatures were measured continuously. The trajectories of the right upper limb were recorded with a 3D motion analysis system. Muscular strain (averaged EMG, a-EMG) and EMG gaps in eight muscles of the right upper limb were measured. End point excursion depicting the ability to maintain dynamic balance was measured before and after each experiment. Leg cooling decreased significantly (P < 0.05) the muscle and the mean skin temperature in C compared with N (6.7 and 2.2°C, respectively). No marked changes in the trajectories or EMG activity were observed between the different environmental conditions. The end point excursion was significantly (P < 0.05) reduced in C compared with N and a positive correlation between excursion and muscle temperature was found at the end of the working period in C. In conclusion, local leg cooling did not affect upper limb muscle function or trajectories, but ability to maintain dynamic balance was reduced.
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| 53. |
- Piedrahita, Hugo, et al.
(författare)
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Effects of cooling and clothing on vertical trajectories of the upper arm and muscle functions during repetitive light work
- 2008
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 104:2, s. 183-191
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Tidskriftsartikel (refereegranskat)abstract
- The present study was designed to find out if cooling and/or clothing affect the vertical trajectories and muscle function of the upper arm during repetitive light work. Twelve female subjects performed a one-handed lifting task for 60 min while standing in front of a table with six target angles (30 degrees to 220 degrees ). The experiment was carried out in a climatic chamber in three different conditions: at 10 degrees C (C), at 25 degrees C (TN), and at 10 degrees C dressed in cold-protective clothing (C(p)). Skin and rectal temperatures were measured continuously. The vertical trajectories of the head, shoulder, elbow, and wrist on the right side of the body were recorded. Muscular strain (averaged EMG, a-EMG) and EMG gaps in eight muscles on the right upper arm were measured. The variation of the vertical trajectory amplitude of the upper arm measured from the elbow was significantly higher (at 200 degrees ) both at C and C(p) (50 and 25% respectively) and in shoulder (at 220 degrees angle) at C (33%) compared with TN (P < 0.05). Both C and C(p) increased a-EMG and reduced the number and duration of EMG gaps significantly in all muscles studied. In conclusion, in repetitive tasks the high mean vertical trajectory and changes in the amplitude of the trajectory of the upper arm at C and C(p) compared with TN were associated with increased muscular strain and reduced number of EMG gaps (more continuous activation of given muscle fibers). The changes in trajectories may serve as indicator of a risk for local muscle fatigue
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| 54. |
- Richardson, Matt, et al.
(författare)
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Hypoxia augments apnea-induced increase in hematocrit and hemoglobin concentration
- 2009
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 105:1, s. 63-68
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Tidskriftsartikel (refereegranskat)abstract
- Increased hemoglobin concentration (Hb) and hematocrit (Hct) attributable to spleen contraction raises blood gas storage capacity during apnea, but the mechanisms that trigger this response have not been clarified. We focused on the role of hypoxia in triggering these Hb and Hct elevations. After horizontal rest for 20 min, 10 volunteers performed 3 maximal apneas spaced by 2 min, each preceded by a deep inspiration of air. The series was repeated using the same apneic durations but after 1 min of 100% oxygen breathing and oxygen inspiration prior to apneas. Mean apneic durations were 150s, 171s, and 214s for apneas 1, 2, and 3, respectively. Relative to pre-apnea values, the mean post-apneic arterial oxygen saturation nadir was 84.7% after air and 98% after oxygen. A more pronounced elevation of both Hb and Hct occurred during the air trial: after apnea 1 with air, mean Hb had increased by 1.5% (P<0.01), but no clear increase was found after the first apnea in with oxygen. After the third apnea with air Hb had increased by 3.0% (P<0.01), and with oxygen by 2.0% (P<0.01). After the first apnea with air Hct had increased by 1.9% (P<0.01) and after 3 apneas by 3.0% (P<0.01), but Hct did not change significantly in the oxygen trial. In both trials, Hb and Hct were at pre-apneic levels 10 min after apneas. Diving bradycardia during apnea was the same in both trials. We concluded that hypoxia is essential in inducing spleen-related Hb and Hct increase during apnea.
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| 55. |
- Richardson, Matt, et al.
(författare)
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Short-term effects of normobaric hypoxia on the human spleen
- 2008
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 104:2, s. 395-399
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Tidskriftsartikel (refereegranskat)abstract
- Spleen contraction resulting in an increase in circulating erythrocytes has been shown to occur during apnea. This effect, however, has not previously been studied during normobaric hypoxia whilst breathing. After 20 min of horizontal rest and normoxic breathing, five subjects underwent 20-min of normobaric hypoxic breathing (12.8% oxygen) followed by 10 min of normoxic breathing. Ultrasound measurements of spleen volume and samples for venous hemoglobin concentration (Hb) and hematocrit (Hct) were taken simultaneously at short intervals from 20 min before until 10 min after the hypoxic period. Heart rate, arterial oxygen saturation (SaO2) and respiration rate were recorded continuously. During hypoxia, a reduction in SaO2 by 34% (P < 0.01) was accompanied by an 18% reduction in spleen volume and a 2.1% increase in both Hb and Hct (P < 0.05). Heart rate increased 28% above baseline (P < 0.05). Within 3 min after hypoxia SaO2 had returned to pre-hypoxic levels, and spleen volume, Hb and Hct had all returned to pre-hypoxic levels within 10 min. Respiratory rate remained stable throughout the protocol. This study of short-term exposure to eupneic normobaric hypoxia suggests that hypoxia plays a key role in triggering spleen contraction and subsequent release of stored erythrocytes in humans. This response could be beneficial during early altitude acclimatization.
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| 56. |
- Sandsjö, Leif, 1958, et al.
(författare)
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Comparative assessment of study groups of elderly female computer users from four European countries: questionnaires used in the NEW study.
- 2006
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 96, s. 122-126
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Tidskriftsartikel (refereegranskat)abstract
- There is a lack of consistent and comprehensive questionnaire forms for the studies of factors associated with work-related musculoskeletal disorders at the European level. One of the results of the EU-funded project, neuromuscular assessment in the elderly worker (NEW), is a set of questionnaires for the screening of musculoskeletal status and the studies of factors that are believed to affect musculoskeletal health. The questionnaires have been used among elderly women (45+) in different occupations and organisations in Denmark, The Netherlands, Sweden and Switzerland. The aim of this short communication is to present the questionnaires used in the NEW study and to evaluate the appropriateness of pooling data gathered in each participating country into a common database. It is concluded that although differences exist among the study samples, these are not of such a magnitude or pattern that data from the four groups cannot be pooled. The questionnaires are available in Danish, Dutch, English, German and Swedish.
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| 57. |
- Schagatay, Erika, et al.
(författare)
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Hematological response and diving response during apnea and apnea with face immersion
- 2007
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 101:1, s. 125-132
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Tidskriftsartikel (refereegranskat)abstract
- Increased hematocrit (Hct) attributable to splenic contraction accompanies human apneic diving or apnea with face immersion. Apnea also causes heart rate reduction and peripheral vasoconstriction, i.e., a cardiovascular diving response, which is augmented by face immersion. The aim was to study the role of apnea and facial immersion in the initiation of the hematological response and to relate this to the cardiovascular diving response and its oxygen conservation during repeated apneas. Seven male volunteers performed two series of five apneas of fixed near-maximal duration: one series in air (A) and the other with facial immersion in 10°C water (FIA). Apneas were spaced by 2 min and series by 20 min of rest. Venous blood samples, taken before and after each apnea, were analysed for Hct, hemoglobin concentration (Hb), lactic acid, blood gases and pH. Heart rate, skin capillary blood flow and arterial oxygen saturation were continuously measured non-invasively. A transient increase of Hct and Hb by approximately 4% developed progressively across both series. As no increase of the response resulted with face immersion, we concluded that the apnea, or its consequences, is the major stimulus evoking splenic contraction. An augmented cardiovascular diving response occurred during FIA compared to A. Arterial oxygen saturation remained higher, venous oxygen stores were more depleted and lactic acid accumulation was higher across the FIA series, indicating oxygen conservation with the more powerful diving response. This study shows that the hematological response is not involved in causing the difference in oxygen saturation between apnea and apnea with face immersion
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| 58. |
- Schagatay, Erika, et al.
(författare)
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Speed of spleen volume changes evoked by serial apneas
- 2005
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 93:4, s. 447-452
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Tidskriftsartikel (refereegranskat)abstract
- Diving mammals may enhance dive duration by injecting extra erythrocytes into the circulation by spleen contraction. This mechanism may also be important for apneic duration in humans. We studied the speed and magnitude of spleen volume changes evoked by serial apneas, and the associated changes in hematocrit (Hct) and hemoglobin (Hb) concentration, diving response and apneic duration. Three maximal apneas separated by 2 min rest elicited spleen contraction in all ten subjects, by a mean of 49 (27) ml (18%; P<0.001). During the same period, Hct and Hb rose by 2.2 and 2.4% respectively (P<0.01 and P<0.001), and apneic duration rose by 20 s (22% P<0.05). The mean heart rate reduction of the diving response was 15%, which remained the same throughout the apnea series. While the diving response was completely reversed between the apneas, spleen size was not recovered until 8–9 min after the final apnea corresponding with recovery of Hct and Hb. Thus, although the spleen contraction may be associated with the cardiovascular diving response, it is likely to be triggered by different mechanisms, and it may remain activated between dives spaced by short pauses. The two adjustments may provide a fast, quickly reversed, and a slow, but long-lasting, way of shifting to a diving mode in humans
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| 59. |
- Stenevi Lundgren, Susanna, et al.
(författare)
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Effects of a daily school based physical activity intervention program on muscle development in prepubertal girls.
- 2009
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Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6327 .- 1439-6319. ; Nov 19, s. 533-541
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Tidskriftsartikel (refereegranskat)abstract
- This 12-month prospective controlled intervention evaluated the effect of a general school based physical activity program on muscle strength, physical performance and body composition in prepubertal girls. Fifty-three girls aged 7-9 years involved in a school based exercise program [40 min/day of general physical activity per school day (200 min/week)] were compared with 50 age-matched girls who participated in the general Swedish physical education curriculum (mean 60 min/week). Body composition (DXA), isokinetic peak torque (PT) of the knee extensors and flexors at 60 and 180 degrees /s, and vertical jump height (VJH) were assessed at baseline and 12 months. The annual gain in weight was similar between the groups, but there was a greater increase in total body and regional lean mass (P < 0.05) and fat mass (P < 0.01) in the exercise group. Mean gains in knee extensor PT at 60 and 180 degrees /s were 7.0-7.6% greater in the exercise group (P ranging <0.05-<0.001). No significant differences were detected in VJH. In conclusion, increasing school based physical education to at least 3 h/week provides a feasible strategy to enhance the development of muscle strength and lean mass in prepubertal girls.
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| 60. |
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| 61. |
- Terzis, Gerasimos, et al.
(författare)
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Resistance exercise-induced increase in muscle mass correlates with p70S6 kinase phosphorylation in human subjects.
- 2008
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 102:2, s. 145-52
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present study was to investigate the possible relationship between a change in Thr(389) phosphorylation of p70S6 kinase (p70(S6k)) after a single resistance training session and an increase in skeletal muscle mass following short-term resistance training. Eight male subjects performed an initial resistance training session in leg press, six sets of 6RM with 2 min between sets. Muscle biopsies were obtained from the vastus lateralis before (T1) and 30 min after the initial training session (T2). Six of these subjects completed a 14-week resistance-training programme, three times per week (nine exercises, six sets, 6RM). A third muscle biopsy was obtained at the end of the 14-week training period (T3). One repetition maximum (1RM) squat, bench press and leg press strength as well as fat-free mass (FFM, with dual energy X-ray absorptiometry) were determined at T1 and T3. The results show that the increase in Thr(389) phosphorylation of p70(S6k) after the initial training session was closely correlated with the percentage increase in whole body FFM (r = 0.89, P < 0.01), FFM(leg) (r = 0.81, P < 0.05), 1RM squat (r = 0.84, P < 0.05), and type IIA muscle fibre cross sectional area (r = 0.82, P < 0.05) after 14 weeks of resistance training. These results may suggest that p70(S6k) phosphorylation is involved in the signalling events leading to an increase in protein accretion in human skeletal muscle following resistance training, at least during the initial training period.
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| 62. |
- Tesch, Per A, et al.
(författare)
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Effects of 17-day spaceflight on knee extensor muscle function and size. : European journal of applied physiology
- 2005
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 93:4, s. 463-468
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Tidskriftsartikel (refereegranskat)abstract
- It is generally held that space travelers experience muscle dysfunction and atrophy during exposure to microgravity. However, observations are scarce and reports somewhat inconsistent with regard to the time course, specificity and magnitude of such changes. Hence, we examined four male astronauts (group mean 43 years, 86 kg and 183 cm) before and after a 17-day spaceflight (Space Transport System-78). Knee extensor muscle function was measured during maximal bilateral voluntary isometric and iso-inertial concentric, and eccentric actions. Cross-sectional area (CSA) of the knee extensor and flexor, and gluteal muscle groups was assessed by means of magnetic resonance imaging. The decrease in strength (P<0.05) across different muscle actions after spaceflight amounted to 10%. Eight ambulatory men, examined on two occasions 20 days apart, showed unchanged (P>0.05) muscle strength. CSA of the knee extensor and gluteal muscles, each decreased (P<0.05) by 8%. Knee flexor muscle CSA showed no significant (P>0.05) change. The magnitude of these changes concord with earlier results from ground-based studies of similar duration. The results of this study, however, do contrast with the findings of no decrease in maximal voluntary ankle plantar flexor force previously reported in the same crew.
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| 63. |
- Thorn, Stefan, et al.
(författare)
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A comparison of muscular activity during single and double mouse clicks
- 2005
-
Ingår i: European Journal of Applied Physiology. - : Springer. - 1439-6319 .- 1439-6327. ; 94:1, s. 158-167
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Tidskriftsartikel (refereegranskat)abstract
- Work-related musculoskeletal disorders (WMSDs) in the neck/shoulder region and the upper extremities are a common problem among computer workers. Occurrences of motor unit (MU) double discharges with very short inter-firing intervals (doublets) have been hypothesised as a potential additional risk for overuse of already exhausted fibres during long-term stereotyped activity. Doublets are reported to be present during double-click mouse work tasks. A few comparative studies have been carried out on overall muscle activities for short-term tasks with single types of actions, but none on occurrences of doublets during double versus single clicks. The main purpose of this study was to compare muscle activity levels of single and double mouse clicks during a long-term combined mouse/keyboard work task. Four muscles were studied: left and right upper trapezius, right extensor digitorum communis (EDC) and right flexor carpi ulnaris. Additionally, MU activity was analysed through intramuscular electromyography in the EDC muscle for a selection of subjects. The results indicate that double clicking produces neither higher median or 90th percentile levels in the trapezius and EDC muscles, nor a higher disposition for MU doublets, than does single clicking. Especially for the 90th percentile levels, the indications are rather the opposite (in the EDC significantly higher during single clicks in 8 of 11 subjects, P < 0.05). Although it cannot be concluded from the present study that double clicks are harmless, there were no signs that double clicks during computer work generally constitute a larger risk factor for WMSDs than do single clicks.
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| 64. |
- Vedam, Hima, et al.
(författare)
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Short-term hypoxia reduces arterial stiffness in healthy men.
- 2009
-
Ingår i: European journal of applied physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 105:1, s. 19-25
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Tidskriftsartikel (refereegranskat)abstract
- This study examined the effects of hypoxia (80% arterial oxyhaemoglobin saturation for 20 min) and the accompanying changes in heart rate and blood pressure on two components of arterial stiffness in healthy men. Augmentation index (AIx) and time to reflection (Tr) representing measures of muscular artery and aortic stiffness, respectively, were continuously measured. At first, subjects were exposed to either hypoxia (n = 12) or room air (n = 5). During early hypoxia AIx increased by 6% before decreasing to baseline. After hypoxia AIx decreased by a further 6%. In contrast there was no change in Tr. Six subjects were then exposed to hypoxia following infusion with the nitric oxide (NO) synthase inhibitor NG-mono-methyl-L: -arginine (L-NMMA) or saline. During hypoxia AIx decreased by 12% following saline but increased by 14% after L-NMMA and Tr did not change. These findings suggest that hypoxia may induce NO-mediated vasodilatation of small muscular arteries but not the aorta.
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| 65. |
- Verney, Julien, et al.
(författare)
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Combined lower body endurance and upper body resistance training improves performance and health parameters in healthy active elderly
- 2006
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 97:3, s. 288-297
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- We investigated the effects of combined lower body (LB) endurance and upper body (UB) resistance training on endurance, strength, blood lipid profile and body composition in active older men. Ten healthy still active men (73+/-4 years, V(O2) peak: 36 (31-41) ml min-1 kg-1) were tested before and after 14 weeks of combined training (3 times week-1). Training consisted of 3x12 min of high intensity interval training on a bicycle for endurance interspersed by 3x12 min of UB resistance exercises. V(O2) peak during leg cycling and arm cranking, isokinetic torque of knee extensor and shoulder abductor and the cross-sectional area (CSA) of several muscles from UB and LB were measured. Sagittal abdominal diameter (SAD) and abdominal fat area were measured on MRI scans. Total body composition was assessed by hydrostatic weighing (HW) and dual-energy X-ray absorptiometry (DEXA). Blood lipid profile was assessed before and after training. By the end of the training period, V(O2) peak (l min-1) increased significantly by 9 and 16% in leg cycling and arm cranking tests, respectively. Maximal isokinetic torque increased both for the knee extensor and shoulder abductor muscle groups. CSA increased significantly in deltoid muscle. Percentage of body fat decreased by 1.3% (P<0.05) and abdominal fat and SAD decreased by 12 and 6%, respectively (P<0.01). There was also a significant decrease in total cholesterol and low-density lipoprotein. Thus, combined LB endurance and UB resistance training can improve endurance, strength, body composition and blood lipid profile even in healthy active elderly.
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| 66. |
- Vollenbroek-Hutten, M., et al.
(författare)
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Are changes in pain induced by myofeedback training related to changes in muscle activation patterns in patients with work-related myalgia?
- 2006
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6319 .- 1439-6327. ; 96:2, s. 209-215
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this explorative study was to investigate to what extent changes in perceived pain, induced by myofeedback training, are correlated to changes in muscle activation patterns. Thirty subjects with work-related myalgia received myofeedback training. Before (T0), directly after (T1) and 4 weeks or, in a subset of patients, 3 months after (T2) this training, surface electromyography (sEMG) measurements of the upper trapezius muscle were performed during standardized computer tasks; a typing and a stress task. Besides this, visual analogue scales (VAS) were filled in to assess the levels of pain in the neck and shoulders. From the sEMG, root mean square (RMS) and relative rest time (RRT, i.e. the percentage of time RMS is below a certain threshold) were used for data analysis. The relationships between RRT, RMS and VAS at T0 as well as for the changes between T1-T0 and T2- T0 were investigated using Spearman correlation coefficients. The results revealed no significant correlations between VAS and RMS both at baseline (range R = -0.22 to 0.17) and for the observed changes (range R = -0.33 to 0.32). Also, for VAS and RRT, low correlations were found for baseline (range R = -0.27 to 0.21) and for changes between T1-T0 (range R = -0.02 to 0.38). However, for the changes between T2-T0, correlation coefficients for the VAS for the shoulder and the RRT of the right trapezius during both the typing and stress tasks were significant at the P = 0.05 level, whereas the correlation coefficients for the VAS for the neck and both the left and right trapezii during the stress task approached significance (P = 0.05 and P = 0.1, respectively). These results suggest that decreases in pain observed at long term follow up after myofeedback training might occur as a result of an increased ability to relax but not as a result of decreased muscle activation level. However, the largest correlation found was 0.6. This means that the maximal explained variance (R2) is low (36%), and that there are also other processes than the changes in muscle activation that contribute to changes in perceived pain.
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| 67. |
- Wein, Jens, et al.
(författare)
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Cardiac and ventilatory responses to apneic exercise
- 2007
-
Ingår i: European Journal of Applied Physiology. - : Springer Science and Business Media LLC. - 1439-6327 .- 1439-6319. ; 100:6, s. 637-644
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Tidskriftsartikel (refereegranskat)abstract
- This study was to elucidate the physiological effects of dynamic apneas, as performed as a discipline in breath-hold diving for recreational or competitive purposes. Therefore, cardiovascular and respiratory effects of apneas with simultaneously initiated exercise were investigated in ten trained breath-hold divers. They performed maximum duration apneas with face immersion (26 degrees C) under rest and exercise (40 W, 80 W and 120 W) on a cycle ergometer in the laboratory. Apneic time, heart rate (HR), mean arterial pressure (MAP), arterial oxygen saturation and O(2) [Formula: see text] and CO(2) exchange were measured. All end-apnea heart rates were lower than corresponding control values. Higher workloads increased the initial rise in HR and delayed the onset of bradycardia. After an initial drop, MAP rose to 150% of control towards the end of apnea. Apneic [Formula: see text] was reduced by 25% during exercise and by 40% during resting apneas compared to eupneic control values. It was concluded that magnitude and time course of diving bradycardia depend on work intensity. Higher workloads delay the onset and attenuate HR reduction, presumably due to increased sympathetic activity. It was also found that apnea with simultaneously initiated exercise has an O(2) conserving effect compared to eupneic exercise. Although aimed to be a realistic approach to breath-hold diving, the study has certain methodological limitations in terms of body-immersion (hydrostatic pressure effects) and body-cooling effects due to conduction of the experiments in a laboratory set-up.
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| 68. |
- Thorell, Daniel, et al.
(författare)
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Strenuous exercise increases late outgrowth endothelial cells in healthy subjects
- 2009
-
Ingår i: European Journal of Applied Physiolology. - 1439-6327. ; 107:4, s. 481-8
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Tidskriftsartikel (refereegranskat)abstract
- Endothelial progenitor cells (EPCs) and late outgrowth endothelial cells (OECs) seem to play an important role in vessel formation. While EPCs seem to exert their function mainly through a paracrine effect, the OECs can develop into mature endothelial cells and form tubular structures. Exercise is known to increase angiogenic factors that can mobilize EPCs; however, the effect on OECs is not known. We investigated the response to a single session of strenuous exercise on OECs, vascular endothelial growth factor (VEGF) and inflammatory cell levels in the healthy. Eleven healthy subjects performed 1 h of spinning exercise. Blood samples were collected at 1, 6, 24 and 48 h post-exercise for cell culture and biochemical analysis. OEC colonies doubled one hour after the spinning session (baseline 4.5 +/- 4.3 vs. 9.0 +/- 3.7, P < 0.05). Serum VEGF increased from 194 +/- 107 pg/ml at baseline to 224 +/- 111 pg/ml after 1 h, p = ns and neutrophilic granulocytes increased from 3.73 +/- 1.38 at baseline to 9.08 +/- 10.5 at 1 h (P < 0.01). The increased levels of OECs, VEGF and neutrophilic granulocytes declined gradually at the following time points. VEGF levels and neutrophilic granulocytes were highly correlated to OEC levels, r = 0.903 (VEGF) and r = 0.85 (neutrophilic granulocytes), respectively. Strenuous physical activity increases OEC colonies and is correlated to serum VEGF and neutrophilic granulocytes levels. An acute exercise-induced inflammatory response might be responsible for the VEGF release and subsequent increase of OECs. The clinical importance of these findings remains to be elucidated.
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| 69. |
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