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The effect of a comprehensive rehabilitation programme, including diet therapy, was studied in overweight male myocardial infarction (MI) patients randomly assigned to a rehabilitation group (n = 69) and a control group (n = 64). The results show a mean weight decrease of 3.8 kg in the rehabilitation group and a mean weight increase of 1.1 kg in the control group (t = -5.78, p less than 0.001). The proportion of patients reducing their weight more than 5 kg was 33% in the rehabilitation group and 5% in the control group (chi 2 = 15.6, p less than 0.001). Patient characteristics which significantly affected the weight change by univariate analysis were age, level of overweight, smoking habits, employment situation and social problems. Multivariate analyses yielded a two-variable model with moderate explanatory power in the rehabilitation group. The model includes the variables Body Mass Index and cessation of smoking before MI.

The recent findings that bicycle exercise training may reduce the number of swollen joints in patients with rheumatoid arthritis (RA) stimulated us to examine the possibility that this was mediated through exercise-induced immunomodulation. The effect of a single bout of physical exercise on blood mononuclear subsets, proliferative responses and natural killer (NK) cell activity was determined. Six patients with moderately active RA for 20 years exercised for 27 min on a bicycle, the work intensity being estimated at 68% of max VO2max. Blood samples were collected before and during the last minutes of exercise, as well as 2 h afterwards. During bicycle exercise the proportion of T cells (DC3+ cells) declined, mainly because of a fall in T helper cells (DC4+ cells). The proportion of NK cells (CD16+ cells) increased during work, but reverted afterwards. The monocytes (CD14+ cells) did not change; B cells (CD20+ cells) declined slightly during exercise and reverted later. No change in PHA-, PPD- and Unstimulated BMNC proliferation occurred during exercise. Two hours after exercise, PPD- and IL-2-induced proliferation increased significantly, except for the PHA-stimulated response. The NK cell activity increased only significantly during exercise when the cells were preincubated with indomethacin, and returned to normal 2 h afterwards. This shows that brief, moderate exercise by patients with RA alters the composition of blood mononuclear cell subsets and cell functions. The clinical significance of this immunomodulation remains to be elucidated.

Cellular immunity was measured under resting conditions in 29 highly trained male racing cyclists during a period of low training intensity (winter), and in 15 untrained people. Fifteen of the cyclists were reexamined during a period of high training intensity (summer) together with 10 of the untrained people. Data on lymphocyte subpopulations, natural killer cell activity and lymphocyte proliferative responses were obtained. Changes in any of these immune parameters from low to high training seasons did not differ significantly between the trained and untrained people. The natural killer cell activity was significantly higher in the cyclists, both during the period of low training intensity (39.2±11.6%vs 30.9±6.4%) and during the period of high training intensity (55.2±18.4% vs 33.6±20.3%). Leucocyte, lymphocyte and neutrophil concentrations did not differ between the two groups. The blood mononuclear cell (BMNC) subsets, including CD3+, CD4+, CD8+ and CD16+ cells, and the BMNC proliferative responses following stimulation with either interleukin 2, purified derivative of tuberculin or phytohaemagghitinin did not differ significantly between the groups.

Exercise stimulates the production and release of interleukin-6 (IL-6) from skeletal muscle. Glutamine is also synthesized in skeletal muscle and is involved in protein synthesis within this tissue. During exercise, plasma levels of glutamine decline, and this may affect the concentration of plasma IL-6 via a decrease in IL-6 synthesis and release from muscle. We hypothesized that glutamine supplementation would attenuate the exercise-induced decrease in plasma glutamine concentration and, thus, further enhance levels of plasma IL-6. Eight healthy men participated in a randomized, double-blind, crossover study in which they performed 2 h of cycle ergometry at 75% of peak O2 uptake. They received glutamine, glutamine-rich protein, or placebo supplementation at intervals during and 2 h after exercise. Exercise induced an 11-fold increase in plasma IL-6, which was further enhanced by glutamine (18-fold) and glutamine-rich protein (14-fold) supplementation, administered at doses that attenuated the exercise-induced decrease in plasma glutamine concentration.

To examine the plasma interleukin (IL)-6 response in elderly (E) and young (Y) humans, 10 E and 10 Y subjects completed 60 min of eccentric lower limb exercise at the same relative oxygen uptake. Plasma IL-6 was measured before, immediately after, and 5 days into recovery from exercise, as were the biochemical markers of muscle damage, creatine kinase (CK), and myoglobin. In both groups, IL-6 increased ( P < 0.05) immediately after exercise and peaked 4 h after exercise at 4.35 ± 1.7 vs. 5.05 ± 3.17 pg/ml for E and Y subjects, respectively. However, the increase in IL-6 in both groups was modest relative to the increases in CK peaking at 539 ± 413 vs. 10,301 ± 5,863 U/l for E and Y subjects, respectively. In addition, the increase in IL-6 was less pronounced ( P < 0.05) in E subjects compared with Y subjects. These results suggest that IL-6 increases progressively after eccentric exercise, suggesting that this increase is related to muscle damage. However, the modest increase in IL-6, despite large increases in CK, suggests that the IL-6 response to muscle damage does not make an important contribution to the large increase in IL-6 observed during concentric exercise of long duration. Our data also suggest that aging may be associated with impaired repair mechanisms for exercise-induced muscle damage.

Prolonged strenuous exercise is followed by a temporary functional immune impairment. Low numbers of CD4+T helper (Th) and CD8+ T cytotoxic (Tc) cells are found in the circulation. These cells can be divided according to their cytokine profile into type 1 (Th1 and Tc1), which produce interferon-γ and interleukin (IL)-2, and type 2 (Th2 and Tc2) cells, which produce IL-4. The question addressed in the present study was whether exercise affected the relative balance between the circulating levels of these cytokine-producing T cells. Nine male runners performed treadmill running for 2.5 h at 75% of maximal oxygen consumption. The intracellular expression of cytokines was detected following stimulation with ionomycin and phorbol 12-myristate 13-acetate in blood obtained before, during, and after exercise. The percentage of type 1 T cells in the circulation was suppressed at the end of exercise and 2 h after exercise, whereas no changes were found in the percentage of type 2 T cells. Plasma epinephrine correlated negatively with the percentage of circulating CD8+ T cells producing IL-2, whereas peak IL-6 correlated with the percentage of CD8+ IL-4-producing T cells in the circulation. Peak plasma IL-6 correlated with plasma cortisol postrunning. In conclusion, the postexercise decrease in T lymphocyte number is accompanied by a more pronounced decrease in type 1 T cells, which may be linked to high plasma epinephrine. Furthermore, IL-6 may stimulate type 2 T cells, thereby maintaining a relatively unaltered percentage of these cells in the circulation compared with total circulating lymphocyte number.

Exercise induces increased levels of plasma interleukin-6 (IL-6) as well as changes in the concentration of lymphocytes and neutrophils. The aim of this study was to investigate a possible role for epinephrine. Seven healthy men participated in an exercise experiment. One month later they received an epinephrine infusion. The exercise consisted of treadmill running at 75% of maximal O2 consumption for 2.5 h. The infusion trial consisted of 2.5 h of epinephrine infusion calculated to reach the same plasma epinephrine levels seen during the exercise experiment. The plasma concentration of IL-6 increased 29-fold during exercise, with peak levels at the end of exercise. The increase in plasma IL-6 during epinephrine infusion was only sixfold, with the peak value at 1 h after infusion. The lymphocyte concentration increased to the same levels during exercise and epinephrine infusion. The lymphocyte count decreased more in the postexercise period than after epinephrine infusion. The neutrophil concentration was elevated threefold in response to exercise, whereas no change was found in response to epinephrine infusion. In conclusion, the exercise-induced increase in plasma IL-6 could not be mimicked by epinephrine infusion. However, epinephrine induced a small increase in IL-6 and may, therefore, partly influence the plasma levels of IL-6 during exercise. In addition, the results support the idea that epinephrine plays a role in exercise-induced changes in lymphocyte number, whereas epinephrine does not mediate exercise-induced neutrocytosis.

1. In human pennate muscle, changes in anatomical cross-sectional area (CSA) or volume caused by training or inactivity may not necessarily reflect the change in physiological CSA, and thereby in maximal contractile force, since a simultaneous change in muscle fibre pennation angle could also occur. 2. Eleven male subjects undertook 14 weeks of heavy-resistance strength training of the lower limb muscles. Before and after training anatomical CSA and volume of the human quadriceps femoris muscle were assessed by use of magnetic resonance imaging (MRI), muscle fibre pennation angle (theta(p)) was measured in the vastus lateralis (VL) by use of ultrasonography, and muscle fibre CSA (CSA(fibre)) was obtained by needle biopsy sampling in VL. 3. Anatomical muscle CSA and volume increased with training from 77.5 +/- 3.0 to 85.0 +/- 2.7 cm(2) and 1676 +/- 63 to 1841 +/- 57 cm(3), respectively (+/- S.E.M.). Furthermore, VL pennation angle increased from 8.0 +/- 0.4 to 10.7 +/- 0.6 deg and CSA(fibre) increased from 3754 +/- 271 to 4238 +/- 202 microm (2). Isometric quadriceps strength increased from 282.6 +/- 11.7 to 327.0 +/- 12.4 N m. 4. A positive relationship was observed between theta(p) and quadriceps volume prior to training (r = 0.622). Multifactor regression analysis revealed a stronger relationship when theta(p) and CSA(fibre) were combined (R = 0.728). Post-training increases in CSA(fibre) were related to the increase in quadriceps volume (r = 0.749). 5. Myosin heavy chain (MHC) isoform distribution (type I and II) remained unaltered with training. 6. VL muscle fibre pennation angle was observed to increase in response to resistance training. This allowed single muscle fibre CSA and maximal contractile strength to increase more (+16 %) than anatomical muscle CSA and volume (+10 %). 7. Collectively, the present data suggest that the morphology, architecture and contractile capacity of human pennate muscle are interrelated, in vivo. This interaction seems to include the specific adaptation responses evoked by intensive resistance training.

Despite full voluntary effort, neuromuscular activation of the quadriceps femoris muscle appears inhibited during slow concentric and eccentric contractions. Our aim was to compare neuromuscular activation during maximal voluntary concentric and eccentric quadriceps contractions, hypothesizing that inhibition of neuromuscular activation diminishes with resistance training. In 15 men, pretraining electromyographic activity of the quadriceps muscles [vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF)] was 17–36% lower during slow and fast (30 and 240°/s) eccentric and slow concentric contractions compared with fast concentric contractions. After 14 wk of heavy resistance training, neuromuscular inhibition was reduced for VL and VM and was completely removed for RF. Concurrently, electromyographic activity increased 21–52, 22–29, and 16–32% for VL, VM, and RF, respectively. In addition, median power frequency decreased for VL and RF. Eccentric quadriceps strength increased 15–17%, whereas slow and fast concentric strength increased 15 and 8%, respectively. Pre- and posttraining median power frequency did not differ between eccentric and concentric contractions. In conclusion, quadriceps motoneuron activation was lower during maximal voluntary eccentric and slow concentric contractions compared with during fast concentric contraction in untrained subjects, and, after heavy resistance training, this inhibition in neuromuscular activation was reduced.

This study was performed in order to investigate the type of T cells recruited to the blood in response to an acute bout of exercise with regard to mean lengths of telomeric terminal restriction fragments (TRF) and surface activation markers and with special emphasis on age-associated differences. Ten elderly and ten young humans performed maximal bicycle exercise. There was no difference in the number of recruited CD4 + and CD8 + cells between the young and elderly group. In both age groups the immediate increases could be ascribed to recruitment of CD28 − cells (CD8 + and CD4 + cells) and memory cells (only CD8 + cells). Furthermore, after exercise mean TRF lengths were significantly reduced in blood mononuclear cells and in CD8 + cells from young subjects and in CD4 + cells from elderly subjects compared with lengths pre-exercise. These findings suggest that the mobilization of T lymphocytes during acute exercise is mainly a redistribution of previously activated cells with an increased replicative story than cells isolated from the blood at rest. Furthermore, elderly humans fulfilling the Senieur protocol have a preserved ability to recruit T lymphocytes in response to acute physical stress.

Sweat secretion is often disturbed in patients with GH secretory disorders. Hyperhidrosis is a classic feature of acromegaly, and it has recently been shown that GH-deficient patients exhibit decreased sweating capacity after pilocarpine stimulation of the skin. Thus, patients with GH-deficiency may be at risk for developing hyperthermia. To pursue this, we performed a controlled study on sweating and body temperature regulation during exercise in the heat in 16 GH-treated GH-deficient patients with normalized insulin-like growth factor-I and insulin-like growth factor/binding protein-3 serum levels [11 with multiple pituitary deficiency (MPD) and 5 with isolated GH deficiency] and in 10 healthy subjects as controls (CTs). Each subject exercised on a bicycle ergometer for 60 min at a workload corresponding to 45% of their individual maximal oxygen consumption (VO2max), in a room maintained at 35 C. GH serum concentrations increased significantly after approximately 10 min of exercise in the CTs (P < 0.001) but remained low in the patients. Body heat storage was significantly higher in the patients compared with the CTs [89 (SE +/- 10) watts (MPD) vs. 37 (SE +/- 8) watts (CTs), P < 0.001]. Consequently, the core temperatures of the patients increased significantly after exercise compared with those of the CTs [38.3 C (0.10 C) (MPD) and 38.1 C (0.06 C) (isolated GH deficiency) vs. 37.5 C (0.2 C) (CTs) (P < 0.004)]. Skin temperature increased significantly during exercise in the patients but remained unaltered in the CTs. Sweat secretion rates, as determined by the pilocarpine method, were significantly lower in the MPD patients [77 (SE +/- 10) mg/30 min] than in the CTs [115 (SE +/- 7) mg/30 min] (P < 0.005). Total body sweating was lower in the patients than in the CTs, although the difference did not reach statistical significance. Significantly reduced estimated evaporative heat loss was demonstrated in the patients compared with the CTs (P < 0.001). In conclusion, 1) decreased sweating, decreased sensitivity of the sweat gland, and impaired thermoregulation are part of the adult GH-deficiency syndrome, and 2) GH-deficient patients are at risk for developing hyperthermia during physical activity in hot environments.

Background The purpose of the study was to investigate if differences of the head and trunk stability and stabilization strategies exist between subjects classified with Generalized Joint Hypermobility and healthy controls during gait. It was hypothesized that joint hypermobility could lead to decreased head and trunk stability and a head stabilization strategy similar to what have been observed in individuals with decreased locomotor performance. Methods A comparative study design was used wherein 19 hypermobile children were compared to 19 control children, and 18 hypermobile adults were compared to 18 control adults. The subjects were tested during normal walking and walking on a line. Kinematics of head, shoulder, spine and pelvis rotations were measured by five digital video cameras in order to assess the segmental stability (angular dispersion) and stabilization strategies (anchoring index) in two rotational components: roll and yaw. Findings Hypermobile children and adults showed decreased lateral trunk stability in both walking conditions. In hypermobile children, it was accompanied with decreased head stability as the head was stabilized by the inferior segment when walking on a line. Several additional differences were observed in stability and stabilization strategies for both children and adults. Interpretation Stability of the trunk was decreased in hypermobile children and adults. This may be a consequence of decreased stability of the head. Hypermobile children showed a different mode of head stabilization during more demanding locomotor conditions indicating delayed locomotor development. The findings reflect that Generalized Joint Hypermobility probably include motor control deficits.

Objective It has recently been shown that patients with growth hormone deficiency have a reduced sweating capacity. We hypothesize that reduced sweating might affect thermoregulation in growth hormone deficiency patients. In the present study we have examined thermoregulation in growth hormone deficiency patients. Design and patients Six adult growth hormone deficiency patients and six matched controls were exposed to a 90-minute heat period (40 degrees C). On a second day the subjects exercised for 30 minutes under standardized conditions. Measurements On both occasions changes in GH secretion, sweating and temperature were registered. Heat storage and evaporation were calculated from these data. Results We found that during the moderate heat exposure, evaporation was less (56.7 vs 115.6 W, P = 0.0037) and heat storage greater (60.7 vs 37.0 W, P = 0.025) in growth hormone deficiency patients compared to their matched controls. Two of the six patients reacted with severe clinical symptoms of heat exhaustion, whereas the controls were unaffected. After exercise the patients reached significantly higher core temperatures than their matched controls (38.1 vs 37.8 degrees C, P = 0.0097). Conclusions Thus, our findings are indicative of a reduced thermoregulatory function in some patients with GH deficiency.

The present study was designed to explain the mechanism of the post-exercise down-regulation of human natural killer (NK) cell activity recently described by us. Fifteen young, healthy volunteers underwent 60 min of bicycle exercise at 75% of maximal oxygen uptake (VO2max). Six of the volunteers were exercised twice with an interval of at least one month. At the second exercise test they received oral indomethacin. Blood samples were collected before and during the last minutes of exercise as well as 2 h and 24 h after work. The NK cell activity (lysis fixed number of mononuclear cells) increased during bicycle exercise, dropped to a minimum 2 h later and returned to pre-exercise levels within 24 h. During bicycle exercise the percentage of NK cells (CD16+ cells) of mononuclear cells increased significantly but returned to normal within 2 h after exercise. Two hours after exercise, however, increased monocyte cell count and neutrophils were found. The in vitro release of prostaglandin E2 from mononuclear cells was increased. Furthermore, the neutrophil chemiluminescence response was also increased in the 2 h post-exercise period; this response is associated with prostaglandin E2 production by neutrophils. Indomethacin, whether administered in vivo or in vitro, fully restored the suppressed post-exercise NK cell activity. Finally, the NK cell activity of monocyte depleted mononuclear cells did not decrease below basal levels after exercise. These findings strongly indicate that prostaglandins released from monocytes and neutrophils are involved in the post-exercise down-regulation of NK cells.

1. This study was performed to test the hypothesis that the exercise-induced increase in circulating cytokine levels is associated with muscle damage. Nine healthy young male subjects performed two high-intensity bicycle exercise trials separated by two weeks. The first trial consisted of 30 min of normal bicycle exercise (concentric exercise), whereas the second consisted of 30 min of braking with reversed revolution (eccentric exercise). The work loads were chosen to give the same increases in heart rate and catecholamine levels in the blood during each trial. 2. Significant increases (P < 0.05) in plasma concentration of creatine kinase (CK), aspartate aminotransferase and alanine aminotransferase were observed only after the eccentric exercise. Furthermore, the level of interleukin-6 (IL-6) in serum increased significantly after the eccentric exercise and was significantly correlated to CK concentration in the following days, whereas no significant changes were found after the concentric exercise. 3. The total concentration of lymphocytes increased significantly (P < 0.05) as a result of eccentric compared with concentric exercise. This was mainly due to a significantly more pronounced recruitment of natural killer (NK) cells and CD8 positive cells (CD8+ cells) during the eccentric trial. However, no significant differences between the two types of work were found in regard to the circulating concentration of monocytes. The concentration of neutrophils was only significantly increased 2 h after the concentric exercise. 4. The finding that high-intensity eccentric exercise caused a more pronounced increase in the plasma level of IL-6, compared with concentric exercise, supports the hypothesis that the post-exercise cytokine production is related to skeletal muscle damage. The fact that no differences between eccentric and concentric exercise were found in the recruitment of most blood mononuclear cell subsets to the blood supports the hypothesis that the exercise-induced increase in plasma catecholamines is a major determinant of the mobilization of these cells into the blood. However, as eccentric exercise caused a more pronounced increase in the concentration of NK cells and CD8+ cells, factors involved in muscle damage may also contribute to the recruitment of these cells.

The present study was designed to test the hypothesis that the exercise-induced changes in blood mononuclear cell (BMNC) subsets, BMNC proliferative responses and lymphokine activated killer (LAK) cell activity are mediated by increased epinephrine concentrations. Healthy male volunteers 1) exercised on a bicycle ergometer (75% of VO2max, 1 h) and 2) on another day were given epinephrine as an intravenous infusion to obtain plasma epinephrine concentrations comparable with those seen during exercise. Blood samples were collected in the basal state, during the last minutes of exercise or epinephrine infusion and 2 h later. During both perturbations the %CD3+ and %CD4+ T cells declined and the %CD16+ NK cells increased. Two h afterwards the CD14+ monocytes increased, while no changes were observed in %CD8+ T cells or %CD20+ B cells. The phytohemagglutinin (PHA) response declined during both epinephrine infusion and exercise experiments. The changes in interleukin-2 (IL-2) effect on proliferation and cytotoxic activity (LAK cell activity) were more pronounced in exercise experiments than during epinephrine. Exercise and epinephrine caused increase in concentrations of lymphocytes and neutrophils, but the changes were more pronounced in exercise experiments. The results indicate that, in response to physical exercise, the rise in plasma epinephrine may contribute to the changes in cellular immunity.

Purpose: Expectations of patients concerning total hip arthroplasty (THA) are related to willingness to undergo surgery and to later satisfaction. Analysis of discrepancies between patient and surgeon expectations before THA should lead to better understand motives of dissatisfaction about surgery, but this question has been seldom studied. Our objectives were to compare surgeons’ and patients’ expectations before THA, using the Hospital for Special Surgery Total Hip Replacement Expectations Survey (THR Survey) and to study factors which affect surgeon-patient agreement. Methods: Adult patients on waiting list for THA in three tertiary care centres were interviewed by phone, to assess their expectations and clinic-demographic characteristics. Surgeons used the same questionnaire to assess their expectations regarding the surgery of each patient. Patients’ and surgeons’ answers on THS questionnaire were compared, and differences between surgeons and patients scores were obtained. Univariate and multivariate analyses were used to test the effect of patients’ characteristics on surgeon-patient differences. Results: The three centres recruited 19 surgeons and 132 patients. Mean age was 62.8±13.7 years, 52% of patients were men. Indication for surgery was osteoarthritis in 82%, avascular necrosis in 12%. Surgeons’ and patients’ expectations scores were respectively 90.9±11.1 and 90.0±11.6 over 100. Mean surgeon-patient difference was close to zero, but surgeons’ and patients’ expectations scores showed little agreement on Bland and Altman graph and intraclass correlation coefficient was low (0.16). Patients expected better results than surgeons concerning exercise and sports. Patients with worse disability or physical quality of life, and patients with higher scores on trust in physician were likely to expect more than their surgeons and vice versa. Patients who were workers or employees were mostly more enthusiastic while patients who had a liberal, senior officer or intermediate occupation were mostly less enthusiastic. Patients with at least one comorbidity were mostly more enthusiastic, while patients with no comorbidity had mostly similar expectations than their surgeons. Conclusions: Surgeons and patients do not agree on what to expect from THA, although there is no systematic bias between them. Patients with higher disability may have unrealistically high expectations.

The regulatory role of synovial fluid monocytes/macrophages from patients with rheumatoid arthritis in terms of B lymphocyte activation was evaluated by a reverse haemolytic plaque-forming cell (PFC) assay. Macrophage-depleted blood mononuclear cells (BMC) failed to respond to pokeweed mitogen (PWM). With autologous synovial fluid macrophages added, the PFC responses of macrophage-depleted BMC increased, and optimal concentration for full restoration of the PFC responses ranged from 8 to 35%. Synovial fluid mononuclear cells (SMC) as well as macrophage-depleted SMC were not able to respond to PWM. Addition of irradiated autologous blood macrophages to SMC did not increase the SMC PFC responses. It is concluded that the regulatory properties of synovial fluid macrophages do not explain the low PFC response of SMC to PWM.

The degree of post treadmill-running decrease in pulmonary function (Exercise-Induced Asthma) in 11 adult asthmatics was compared with the decrease in pulmonary function followed by resting isocapnic hyperventilation. It was checked that ventilation during the hyperventilation was kept identical to the ventilation during treadmill-running by continuous recording of respiratory frequency, minute ventilation, tidal volume and accumulated ventilation. The temperature of the inspired air was identical in the two situations and the relative humidity was 40% during treadmill-running and 15% during hyperventilation. The average accumulated ventilation during treadmill-running and hyperventilation was 411 1/6 min in both events. The decrease in peak expiratory flow after treadmill-running was 25% and after isocapnic hyperventilation 24%. It is concluded that the ventilation is of more importance for the decrease in pulmonary function after exercise, than the work load.

The relationship of maximal oxygen uptake\((\dot V_{O_2 } \max )\) and resting oxygen uptake in two seasons of the year (winter/summer) was investigated in 119 young males. The subjects were conscripts, who were investigated at the calling-up time (winter:n=58). The two groups were comparable with respect to their anthropometric data and smoking habits, as well as their occupational and leisure time activities.\(\dot V_{O_2 }\) max was significantly (p

Bronchial response to 6 min exercise performed as treadmill-walking, treadmill-running, ergometer bicycling and free running were compared in 11 subjects with exercise-induced asthma (EIA). The study was performed under control of air temperature and relative humidity. The three different types of exercise were performed on consecutive days, and the ventilation was monitored using pneumotachography and rating of perceived exertion (RPE). The decrease in peak expiratory flow after treadmill-running was 25.5 +/- 4.5% (mean +/- SEM), after bicycle ergometer exercise 26.0 +/- 3.0%, after treadmill-walking 26.0 +/- 3.0% and after free running 27.0 +/- 3.5%. No statistical difference in bronchial response was demonstrated between the four types of exercise. The total ventilation for the 6 min period of exercise was 421, 411 and 427 litres for treadmill-walking, treadmill-running and bicycle ergometer exercise, respectively. It is concluded that the type of work is of little importance in EIA.

The present study was designed to examine the effect of physical exercise on subsets and proliferative responses of blood mononuclear cells. Sixteen young, healthy volunteers underwent 60 min of bicycle exercise at 75% of maximal oxygen uptake (VO2max). After an interval of at least 1 week, six of the subjects underwent a 60-min back muscle training period at up to 30% of VO2max. Blood samples were collected before and during the last minutes of exercise, as well as 2 and 24 h later. Blood mononuclear cell (BMNC) subpopulations were determined and the proliferative responses after incubation with phytohaemagglutinin (PHA) or purified derivative of tuberculin (PPD), were quantified by [3H]thymidine incorporation. During bicycle exercise the relative blood concentration of T cells (CD3+ cells) declined, mainly due to a fall in T helper cells (CD4+ cells). The natural killer (NK) cell subset (CD16+ cells) increased during work, but reverted after; the monocytes (CD14+ cells) increased 2 h after work, whereas the B-cell subset (CD20+ cells) did not change. BMNC subsets were not significantly changed by back muscle exercise. The PHA-induced proliferative response decreased during bicycle exercise, whereas the PPD-induced response did not change. No significant changes occurred during back muscle exercise. Investigation of subgroups after incubation with [3H]thymidine showed that the proliferative response per CD4+ cell did not change in relation to exercise, but the contribution of the CD4+ subgroup to proliferation declined during bicycle exercise due to the decreased proportion of CD4+ cells. The suppression of the PHA response during bicycle exercise can be explained in part by a relative fall in CD4+ cells. The pool sizes of BMNC subfraction may be elicited by increased catecholamine and cortisol levels.

The effect of two types of physical training on patients with perennial asthma were compared in a blind, controlled, randomized study. Eleven of 27 adults with asthma performed a physical training programme which did not change their oxygen consumption (control group). The remaining 16 asthmatics performed a physical training programme which improved their maximal oxygen consumption (training group). Both of the training programmes were performed for 1 hour, twice a week during a period of 2 months. No complications were reported during the performance of the training programmes. The doses of all medicines apart from beta 2-agonist aerosol were unchanged during the training period. The patients inhaled beta 2-agonist aerosol if their peak expiratory flow (PEF) was less than 60% of their maximal PEF. The training group decreased their use of aerosol from an average of 4.94 puffs per day to 3.41 puffs per day (P less than 0.05). The control group did not change their use of beta 2-agonist aerosol significantly. It is concluded that physical exercise which improves the maximal oxygen consumption decreases the use of beta 2-agonist spray and that heavy exercise is well tolerated by asthmatics.

The present study was designed to examine the effect of physical exercise on human natural killer (NK) cells. Six healthy volunteers underwent two different acute physical exercise tests with an interval of at least 1 week: (1) 60 min bicycle exercise at 80% of maximal oxygen uptake (VO2max) and (2) 60 min back-muscle training at up to 29% of VO2max; blood samples were collected before and during the last few minutes of exercise, as well as 2 h and 24 h afterwards. The NK cell activity (lysis/fixed number of mononuclear cells) increased during bicycle exercise, dropped to a minimum 2 h later and returned to pre-exercise levels within 24 h. Back-muscle exercise did not significantly influence NK cell activity. Plasma levels of adrenaline, noradrenaline, and cortisol were elevated during bicycling, but not during back-muscle exercise, indicating that exercise intensity is a determinant of NK cell activity. During bicycle exercise the NK cell subset (CD16- cells) of mononuclear cells increased significantly. Furthermore an improved interleukin 2 (IL-2) boosting of the NK cell activity was found during work as compared to IFN-alpha and indomethacin-enhanced NK cell activity. These results indicate that NK cells with a high IL-2 response capacity are recruited to the peripheral blood during exercise. The decreased NK cell activity demonstrated 2 h after work was probably not due to fluctuations in size of the NK cell pool, since the proportion of CD16+ cells was normal. The finding that indomethacin fully restored the suppressed NK cell activity in vitro and the demonstration of a twofold increase in monocyte (CD20+ cells) proportions 2 h after work, strongly indicate that prostaglandins released by monocytes during the heavy physical exercise are responsible for the down-regulation of the NK cells.

The influence of synovial fluid and blood monocytes on autologous lymphocyte proliferation in vitro was investigated in patients with rheumatoid arthritis (RA) and traumatic synovitis (TS). In cultures stimulated with PHA, PWM and ConA, thymidine incorporation by RA blood mononuclear cells (BMC) increased considerably in most cases after addition of 10% or 30% synovial fluid monocytes and a similar effect was seen after stimulation with Candida extract or PPD. A comparable helper activity was observed after addition of synovial fluid monocytes to monocyte-depleted blood cells in RA. The augmenting effect of synovial fluid monocytes was likewise demonstrated in TS patients. Synovial fluid mononuclear cells (SMC) from RA and TS patients displayed low proliferative responses to PHA and ConA in comparison with BMC, while the responses to microbial antigens were similar or greater. The proliferative activity of SMC or of monocyte-depleted synovial fluid cells after polyclonal and antigenic stimulation was not affected by addition of blood monocytes. This was observed in both RA and TS patients. It is concluded that the regulatory properties of synovial fluid monocytes in RA and TS do not explain the low proliferative responses of SMC to polyclonal activators.

Cross-sectional area of a single fibres and the fibre distribution were measured for the two main types of fibres in needle biopsies from the quadriceps muscle of ten healthy young males. Methodological errors expressed as coefficient of variation (CV) of a single value for the area measurements were analysed and found to be 2.4% including the intraindividual error in handling the planimeter. An inhomogeneity in distribution and size of the fibres within the quadriceps muscle was indicated by a CV within the same section of 6-8% and between repeated biopsies of 15-20%.

In serial cross-sections of human skeletal muscles stained for either NADH-tetrazolium reductase (NADH-TR) or α-glycerophosphate dehydrogenase (α-GPD), a linear relation was found between the total content of enzyme in a cell (expressed as the thickness of the section) and the absorbance of the formazan reaction product formed. Little variation (

Changes in thigh components were investigated with the one-legged inactivity- and training-model using 22 young healthy male soccer players, who for 4-5 weeks had one leg immobilized in a cast. They were investigated before and after the cast period and after 4 weeks' physical training of the inactivated leg. Immobilization induced a significant increase in the subcutaneous thickness and a significant decrease in the circumference of the thigh (p less than 0.01). The calculated lean thigh volume was reduced from 4.93 1 to 4.10 1 (p less than 0.01), whereas the calculated fat thigh volume (1.5 1) was unchanged. The changes reversed after four weeks of progressive dynamic training, but did not reach the pre-immobilized values. Body weight decreased from 73.4 kg to 70.8 kg (p less than 0.01) during the immobilization period and was regained after the training period. The fat fraction of the body was unchanged. It is concluded that the loss in total thigh volume during inactivation in a cast is due to waste of the muscle tissue, and further that this loss is partly concealed by an unchanged fat thigh volume.

Thigh components were estimated by computerized tomography (CT) as well as by anthropometry in two healthy male soccer players (23--29 years), who for 5 weeks had one knee immobilized in a plaster of Paris. The investigations were performed on both thighs just after removal of the cast and after 5 weeks physical training of the inactivated quadriceps muscle. The different components were easily identified on a transverse scan through the middle of the thigh. The quadriceps muscle was 26% smaller after removal of the cast in the inactivated leg as compared with the contralateral leg; no differences were observed in the remaining thigh components. After rehabilitation a specific increase (22%) in the hypotrofic quadriceps muscle was observed, whereas no changes were disclosed in the remaining thigh components. The quadriceps muscle averaged 52% of the lean component in the uninjured thigh, and the subcutaneous part of the total cross-sectional area averaged 15%. The changes in the anthropometrically determined thigh components paralleled those observed by the CT scanning procedure. It is concluded that the loss in the lean thigh volume during immobilization in plaster cast is exclusively due to waste of the quadriceps muscle. CT scanning comprises a new valid tool to study changes in thigh components.

Five young male patients with exercise-induced asthma (EIA) were subjected to graded bicycle exercise with work loads corresponding to 50%, 75% and 120% of the load necessary to elicit maximal oxygen uptake (Vo2 max). The exercise tests were performed after inhalation of salbutamol (Ventoline) as well as after inhalation of saline as control. Additionally two maximal work tests (bicycling and treadmill) were performed without inhalation on a work load corresponding to 100% Vo2 max. Oxygen uptake (Vo2) heart rate (HR), mean blood pressure (MBP), rating of perceived exertion (RPE) as well as arterial concentration of glucose and acid-base variables were measured. Vo2 max during bicycle exercise averaged 3.16 l/min and no significant difference was disclosed between the beta 2-stimulation and the control situations. The coefficient of variation of a single Vo2 max measurement was 4.7%. The maximal treadmill running revealed a significantly higher Vo2 max (3.42 l/min, P less than 0.05) than during bicycling; no EIA was provoked in any of the experiments. After beta 2-stimulation a higher HR and MBP in relation to Vo2 was observed than in the control experiment; however, the slope of HR/Vo2 and MBP/Vo2 relationships was not affected. Normal relationships were observed between Vo2 and work load, ventilation, RPE and acid-base data and these relations were unaffected of beta 2-stimulation. It is concluded, that Vo2 max seems to be within the normal range in asthmatics, provided they are free from attacks.

Multiple sclerosis (MS) seems associated with both the appearance of circulating immune complexes (CIC) and also, to a certain extent, the occurrence of immune complexes (IC) in cerebrospinal fluid (CSF). Furthermore, possible relationships between the occurrence of CIC, variations in the complement levels in serum and the activity of manifestations of the disease have been suggested.

A new device is described for improving the accuracy of measuring the thickness of cryostat sections by the focusing technique in the light microscope. The necessity of such measurements is demonstrated by the great variation (range 2.55 micrometer--11.93 micrometer) in the thickness of serial cross-sections of frozen muscle biopsies from 12 healthy men. The final dehydration of the sections was found to reduce the thickenss of fresh sections by 47%. However, dehydration caused the cross-sectional area to be reduced by only 2.8%.

The relationship of maximal oxygen uptake with tobacco consumption was investigated in sixty-one young males. There was a significant negative correlation between daily consumption of tobacco and measured maximal oxygen uptake (Vo2max) expressed relative to body weight (r = -0.368, P less than 0.01) and to lean body mass (r = -0.497, P less than 0.001), respectively. No correlation could be demonstrated with regard to predicted maximal oxygen uptake (Vo3maxp). No difference was demonstrated between Vo2maxp and Vo2max in nonsmokers and heavy smokers, whereas Vo2maxp was significantly higher (P less than 0.01) in the group of moderate smokers than Vo2max. It is concluded that tobacco smoking decreases Vo2max even in young moderate smokers. Smoking habits should be considered among factors affecting Vo2maxp from cardiac frequency at submaximal levels.

The decrease in pulmonary function, expressed as peak expiratory flow, which is seen in some asthmatics after exercise (exercise-induced asthma (EIA)), has been studied under conditions standardized with regard to ventilation during exercise, room temperature and relative humidity of the inhaled air. Exercise was performed under four different conditions. 1) temperature (T) 15 degrees C and relative humidity (RH) 30%, and 2) T 15 degrees C and RH 70%, 3) T 30 degrees C and RH 30% and 4) T 30 degrees C and RH 70%. Treadmill running was performed on four succeeding days at the same time of day with the four different combined conditions. Identical ventilation during the exercise was secured on each day by monitoring respiratory frequency, tidal volume, minute ventilation and accumulated ventilation. A significantly smaller decrease in pulmonary function occurred when both T and RH were high, whereas the decrease in pulmonary function after exercise was identical when either temperature or relative humidity, or both, were low. It is concluded that the water concentration of the inspired air is negatively correlated to the decrease in pulmonary function after exercise in asthmatics.

The effects of progressive resistance exercise (PRE) training for 4 weeks on the hypotrophic quadriceps muscle were investigated in 23 young healthy male soccer players, who had been immobilized in a plaster cast 4-6 weeks after knee ligament injuries. The subjects were allocated to two training regimes where the injured leg was trained for periods of varying duration, whereas the intensity and frequency of exercise were alike in the two groups. However no significant differences were detected between the two training groups. In the whole material the lean thigh volume of the injured leg increased from 4.09 to 4.47 litres (p less than 0.001), whereas the fat component of the thigh was unchanged. The dynamic strength (1 RM) of the injured leg increased from 14.0 kg to 27.0 kg and amounted to 87% of the control leg after 4 weeks of training. At this time the maximum isometric strength amounted to 114 Nm, which was 63% of strength in the control leg. Succinate dehydrogenase (SDH) in homogenates of muscle biopsy sample increased (i.e. 20%, p less than 0.05) to the same level as found in the control leg. No changes in phosphofructokinase (PFK) were observed. The type I fibre distribution was lower in the immobilized leg than in the control leg. These results indicate that, following muscular hypotrophy resulting from 4-6 weeks of immobilization, dynamic exercise can restore the oxidative potential, whereas the size and strength are only partly recovered.

The relationship of maximal oxygen uptake (VO2 max) with dihydrogenated ergot alkaloids was investigated in twelve young men. They were subjected to graded bicycle exercise with work loads corresponding to 75% and 120% of the load necessary to elicit VO2 max. The exercise tests were performed after intravenous administration of 2 mg dihydroergostin (DE-145) as well as after saline as control, both preparations were given double-blind. VO2 max averaged (SD) 3.36 (0.41) 1/min and no significant difference was disclosed between the DE-145 and the control situation. Normal relationships were observed between VO2 and work load, ventilation, heart rate, cardiac output, central venous pressure and acid-base data, and these relations were unaffected by DE-145 administration. Nausea was constantly seen in all subjects tested with DE-145. It is concluded, that the present dose of DE-145 has no influence on the functional capacity of the oxygen transporting system in sedentary young men.

The activity of blood mononuclear cells (BMC) and synovial fluid mononuclear cells (SMC) from patients with rheumatoid arthritis (RA) and traumatic synovitis (TS) was assessed by means of [14C]thymidine incorporation and production of leukocyte migration inhibitory factor (LIF). When compared with normal controls, spontaneous LIF production by BMC was found in 5 of 9 TS patients, whereas spontaneous LIF production by rheumatoid arthritis BMC and by SMC from both patient groups was infrequently seen. ConA-induced LIF production by BMC and SMC from both patient groups did not differ significantly from that of normal controls. Thymidine incorporation by unstimulated SMC and BMC was low in both patient groups. After stimulation with polyclonal activators, SMC showed significantly reduced proliferation in comparison with BMC, but the responses to microbial antigens were equal to or higher than those of BMC. The proliferative responses of stimulated SMC from TS patients were higher than the responses displayed by stimulated SMC from RA patients.

By means of recently developed immunochemical assays increased levels of the complement C3c and C3d split products were found in synovial fluids of patients with rheumatoid arthritis (RA) as compared with synovial fluids of patients with traumatic synovitis (TS). In plasma, only the C3d levels were significantly increased compared with plasma levels of patients with TS. Both split products were higher in RA synovial fluids (SF) than in RA plasma. A positive correlation between the C3d concentrations in plasma and the presence of IC in serum was found, and between the C3c levels and the concentration of polymorphonuclear cells in SF of RA patients. Due to differences in turn-over of C3c and C3d determination of plasma C3d levels may be a useful parameter for the evaluation of immunological activity in RA, while measurement of C3c in the synovial fluid may elucidate the actual inflammatory activity in the synovial membranes.

Five young males performed dynamic, submaximal contractions to exhaustion with the quadriceps muscle under arterial occlusion. The work load was 14.7 Watt (W). After 10 min rest with intact arterial circulation, the subjects commenced another bout to exhaustion; this process was repeated until a total of 10--16 bouts had been performed. Muscle biopsies were obtained immediately after the second, fifth, eighth, and last bout as well as 30 min after the last bout. The concentrations of adenosine triphosphate (ATP), creatine phosphate (CP), lactate, and glycogen were measured in each sample and some material underwent histochemical analysis. Muscle lactate was highest following the second work bout [22.9 mmol/kg wet weight (ww)] and gradually declined to 7.0 mmol/kg ww by the end of the last bout. CP level was low in all postexercise samples with the exception of a remarkably high CP (11.7 mmol/kg ww) after the last bout. Glycogen utilization tended to parallel muscle lactate levels, the rate of depletion being most rapid initially. Histochemical staining for glycogen depletion revealed that both type I and II fibres were low in glycogen, although type I was depleted most uniformly. In the first work bouts the high lactate and low CP levels in the total muscle could be responsible for the fatigue; none of these factors seem adequate to explain the development of the fatigue experienced in the later work bouts. It is concluded that muscle fatigue in this type of exercise is not related to substrate depletion or accumulation of metabolites, further that the fibre recruitment pattern is determined by the type and relative severity of performed work rather than local metabolic factors.

Isokinetic contraction were performed with the knee extensor muscles in 15 young male soccer players. The measurements were obtained by a modified isokinetic device (Orthotron). In the range of motion the angular velocity was constant from 90 degrees to 20 degrees of knee flexion. The angular velocity could be varied from 30 to 360 degrees/s. The overall variation of the pre-set speed and the peak torque, as estimated from duplicate trials through the whole velocity range, averaged 4% and 5%, respectively. The peak torque decreased linearly with increasing angular velocity in a semilogarithmic scale. An estimate of the peak torque-velocity relationship in an experimental subject was obtained from the slope and the fibre composition in the lateral portion of the quandriceps muscle in this group of subjects especially trained in fast movements. It was concluded that the present applied isokinetic device gives the opportunities to measure force-velocity characteristics in the intact quadriceps muscle of man.

The purpose of this investigation was to study the influence of hyperoxia on catecholamine response to dynamic exercise. While breathing either 21 or 100% O2 seven subjects performed submaximal bicycle exercise. Arterial blood pressure was similar in both exercise experiments. The CO2 output was not influenced by 100% O2 breathing, but increments in plasma lactate concentration were reduced. The increases in plasma norepinephrine and epinephrine concentrations and heart rate were significantly lower during 100% O2 than during 21% O2 breathing. The results suggest that O2 plays an important role in the regulation of sympathetic nervous activity during dynamic exercise in humans.

Eleven adult patients with exercise-induced asthma (EIA) were subjected to swimming and bicycle exercise under controlled conditions regarding temperature and relative humidity of the inhaled air, the respiratory frequency, tidal volume, minute ventilation and the accumulated ventilation. Swimming for 6 min was performed on the first day, and the next day the patients performed bicycle exercise. On both days the temperature of the inhaled air was 23% C and the relative humidity 15%. The average accumulated ventilation for the 6 min of exercise was 404 l for bicycle exercise and 419 l for swimming. The decrease in pulmonary function was 31% after bicycle exercise and 30% after swimming. It is concluded that the stimuli for EIA are equally effective whether exercise is performed in the form of swimming or bicycling.