PubMed HealthSearch

Biomedical subjects

S B Strømme

Publications and source records attributed to S B Strømme.

At least 19 recordsLinked to original sources

Omega-3 fatty acid supplementation does not improve maximal aerobic power, anaerobic threshold and running performance in well-trained soccer players.

In a randomized, placebo-controlled study the effect of 10 weeks of supplementation with either 5.2 g of a concentrated fish oil triglyceride (Triomar) enriched in omega-3 fatty acids (1.60 g/day EPA and 1.04 g/ day DHA) or 5.2 g corn oil (serving as placebo) on maximal aerobic power, anaerobic threshold and running performance was assessed in 28 well-trained male soccer players (18-35 years). Supplements were given as 650-mg capsules. Capsule assignment was randomized to one omega-3 group (n = 15), given eight Triomar capsules per day, and one placebo group (n = 13), given eight capsules of corn oil per day. During the 10-week supplementation period the subjects maintained their usual diets and training regimes. Red blood cell (RBC) osmotic fragility, triglycerides and fatty acid composition in plasma were assessed before and after the supplementation period. The pre- and post-supplementation tests of maximal aerobic power, anaerobic power and running performance showed no significant difference between the two groups. Subjects in the omega-3 group had significantly reduced plasma triglycerides, rose EPA (175%) and DHA (40%) in the total lipid fraction of plasma after supplementation. RBC osmotic fragility did not change. In conclusion, the results do not support the hypothesis that endurance athletes can improve maximal aerobic performance by omega 3-fatty acid supplementation.

Adult

Exercise intensity. An important factor in the etiology of menstrual dysfunction?

UNLABELLED: The objective of this case control study was to compare training activity in female long distance runners with irregular (IR, n = 13) and regular (R, n = 16) menstrual function, especially with regard to exercise intensity. Serum estradiol concentration during the follicular phase was considered normal in the R subjects (31 +/- 6 pg/I). In contrast, the IR runners were clearly hypoestrogenic (11 +/- 1.6 pg/l). The two groups had similar VO2max, anaerobic threshold (AT) and maximal heart frequency (HFmax). In both groups AT was found at 88% of HFmax. The two groups had similar mean race results in half marathons during the previous year. The number of running contests was, however, twice as high in the IR group. A light portable pulse recorder was used to monitor heart rate during 1 week of regular training activity, and during a controlled high intensity work-out. During a week with normal training activity, and equal amount of training at high intensity levels (> 85% HFmax) was performed by the two groups. The amount of training at lower intensities (< 85% HFmax) was, however, more extensive in the group with irregular menstrual function. During the controlled self-administered, high intensity work-out, the amounts of training at and above AT were equal in the two groups. IN CONCLUSION: no difference in extent of high intensity training between long distance runners with regular and irregular menstrual function could be found in the present study group. The IR runners did, however, have significantly more training activity at lower intensity levels, and more frequent race participation.

Anaerobic Threshold

[High altitude training].

The physiological rationale for altitude training is discussed in the article. Acclimatisation to high altitude is accompanied by increases in haematocrit and haemoglobin concentrations, primarily due to a reduction in plasma volume but also to increased erythropoiesis as a result of enhanced erythropoietin release. Owing to the reduction of training load during acclimatisation, maximal aerobic capacity is not necessarily enhanced after high altitude training. However, the increase in the blood lactate concentration during standardised submaximal work has been shown to be significantly reduced--reflecting improved ability to exercise at higher submaximal workloads, as compared with previous ability at lower altitudes. An increase in buffer capacity may be responsible. The importance of a reduced training load and individualised control of training intensity during the acclimatisation period is emphasised. This control takes the form of regular heart rate monitoring and comparison of the blood lactate concentration during training sessions with the individual's pre-established 'lactate profile'. The Norwegian Altitude training project, including the various routines, procedures and problems involved in three successive sojourns at moderate altitudes, is briefly discussed. Finally, a practical approach to altitude training is presented--dealing with training control, iron demand, nutritional advice, fluid intake and recovery. Only top athletes should be selected for training at high altitudes.

Acclimatization

L-tryptophan supplementation does not improve running performance.

In 1988 Segura and Ventura (14) reported that 1.2 g of L-Tryptophan (L-TRY) supplementation increased total exercise time by 49.4% when the subjects were running at 80% of maximal oxygen uptake (VO2max). In human performance research, acute improvements of that category are rather uncommon. Both for this reason and because ingestion of purified L-TRY may have adverse effects, it seemed pertinent to repeat the investigation of Segura and Ventura. Forty-nine well-trained male runners, aged 18-44, with an average maximal aerobic power of 66 (57-78) ml.kg-1.min-1, participated in a randomized double blind placebo (P) study. Each subject underwent four trials on the treadmill. The first two served as learning experience, including measurement of VO2max and anaerobic threshold. During the last two trials the subjects ran until exhaustion at a speed corresponding to 100% of their VO2max-first an initial trial and then after receiving a total of 1.2 g L-TRY or P over a 24 hour period prior to the run. No significant difference between the improvements in the L-TRY and P group could be demonstrated. It is concluded that oral L-TRY supplementation does not enhance running performance.

Adolescent

Comparison of changes in testosterone concentrations after strength and endurance exercise in well trained men.

Changes in the testosterone concentrations after single sessions of endurance and strength training were measured in seven well trained men, experienced in both forms of training. Both training sessions were rated as hard to very hard on the Borg scale. Blood samples for testosterone measurements were taken before, immediately after, and 2, 4 and 6 h after the training sessions as well as the next morning. The mean testosterone concentration increased 27% (P less than 0.02) and 37% (P less than 0.02) during the strength and endurance training session, respectively. Two hours after the training sessions the mean testosterone concentration had returned to the pre-training level and remained at that level for the length of the observation period. There were no significant differences in the changes in testosterone concentration after strength and endurance training but there were large differences in the testosterone response at the level of the individual. A high correlation (r = 0.98; P less than 0.001) for individuals was found between increases in testosterone concentration after strength and after endurance training. It was concluded that the changes in mean testosterone values followed the same timecourse after single sessions of strength and endurance training of the same duration and perceived exertion. The interindividual differences in testosterone response may be of importance for individual adaptation to training.

Adult

Sex differences in performance-matched marathon runners.

Six male and six female runners were chosen on the basis of age (20-30 years) and their performance over the marathon distance (mean time = 199.4, SEM 2.3 min for men and 201.8, SEM 1.8 min for women). The purpose was to find possible sex differences in maximal aerobic power (VO2max), anaerobic threshold, running economy, degree and utilization of VO2max (when running a marathon) and amount of training. The results showed that performance-matched male and female marathon runners had approximately the same VO2max (about 60 ml.kg-1.min-1). For both sexes the anaerobic threshold was reached at an exercise intensity of about 83% of VO2max, or 88%-90% of maximal heart rate. The females' running economy was poorer, i.e. their oxygen uptake during running at a standard submaximal speed was higher (P less than 0.05). The heart rate, respiratory exchange ratio and blood lactate concentration also confirmed that a given running speed resulted in higher physiological strain for the females. The percentage utilization of VO2max at the average marathon running speed was somewhat higher for the females, but the difference was not significant. For both sexes the oxygen uptake at average speed was 93%-94% of the oxygen uptake corresponding to the anaerobic threshold. Answers to a questionnaire showed that the females' training programme over the last 2 months prior to running the actual marathon comprised almost twice as many kilometers of running per week compared to the males (60 and 33 km, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Relationship of high density lipoprotein cholesterol concentration to the duration and intensity of endurance training.

Eleven healthy, male students were studied over period of 8 months. Five were sedentary subjects, and six were competitive cross-country skiers engaged in endurance training of varying amount and intensity. Serum concentration of high density lipoprotein (HDL) cholesterol increased significantly during physical endurance training of low intensity and long duration. With fewer hours of training, but of greater intensity, HDL cholesterol concentration was lower but was still significantly higher than in the control group of sedentary individuals. In conclusion the study suggests that elevated HDL cholesterol concentrations associated with high levels of physical activity are related to both amounts and intensity of the training.

Adult

Excretion of casts and uromucoid in urine after prolonged heavy exercise.

Excretion of uromucoid, albumin and casts in urine were determined in twenty well-trained men, ten aged 20-30 years, and ten aged 50-60 years, before, during and after a 70 km cross country ski race. During the race there was only a slight increase in uromucoid excretion, but a marked increase in the excretion of casts and albumin. The older subjects had a tendency to lower urine output during the race compared to the younger group. Reduction of urine output below ca. 25 ml/h was accompanied by a conspicuous increase in urine cast and albumin concentrations, with only a slight increase in uromucoid concentration, and even a reduction in uromucoid excretion. No significant relationship was found between cast excretion and uromucoid concentration. Thus the gross cylindruria observed during longstanding exercise must be ascribed to other urinary factors facilitating the formation of casts.

Adult

High density lipoprotein cholesterol, total cholesterol and triglycerides in serum after a single exposure to prolonged heavy exercise.

Serum high density lipoprotein (HDL) cholesterol, total serum cholesterol and triglycerides were determined in twenty men before, immediately after, and 1, 2 and 4 days after a 70 km cross-country ski race. HDL cholesterol increased by 12% of the pre-race level immediately after the race, rose further to 17% above the initial level on the following day, and was still elevated 4 days after the race. LDL + VLDL cholesterol, however, showed a tendency to decrease immediately after the race and was reduced by 17% and 11% of the pre-race level on the following 2 days. Triglycerides were reduced by 30% of the initial level immediately after the race, were still low on the following day, but were restored to normal 2 days after the race. It is concluded that a single exposure to prolonged heavy exercise induces changes in the HDL metabolism, showing that the physical exercise per se plays an important role for the increased HDL level seen in well-trained athletes.

Adult

Effects of active, passive or no warm-up on the physiological response to heavy exercise.

Six endurance-trained young men were subjected to a 4 min maximal aerobic treadmill run (100% of VO2 max), after active or passive warm-up or rest on separate days. The increase in body temperature during the active and passive warm-up was controlled, so that the temperature reached the same level, before the subject was exposed to the maximal exercise. On average the rectal temperature rose to 38.3 degrees C (range 38.1-38.6 degrees C). The standard work resulted in a significant higher oxygen uptake, lower lactate concentration and higher blood pH when the work was preceded by active warm-up as compared with passive or no warm-up. The difference in total oxygen uptake during the run between the active and passive warm-up procedure was 0.8 1. No significant difference in minute volume of expired air or respiratory quotient was found. It is concluded that the physiological effects of a thorough active warm-up may be of substantial benefit to athletic performance.

Acid-Base Equilibrium

Pulmonary blood volume and interventricular circulation time in physically trained and untrained subjects.

Resting pulmonary plasma and blood volumes (PPV and PBV), interventricular circulation time (IVCT), cardiac and stroke index (CI and SI), heart rate (HR), total plasma and blood volumes (PV and BV) were determined in athletes (two male groups representing different types of sport activities, and one female group) and compared with those of non-athletes (one male and one female group). In addition to high maximal aerobic power, the athletes were characterized by greater SI, BV and PV and lower resting HR than non-athletes, PPV and PBV were significantly larger and IVCT significantly longer in the trained than in the untrained groups, probably reflecting an improved capacity of the pulmonary circulation. PPV as per cent of PV was almost equal in all the groups, indicating the same distribution of plasma between the pulmonary and systemic circulation. The data also indicate that total blood volume is an important determinant of the magnitude of the pulmonary vascular bed. The increased volume of flowing blood and increased stroke volume in athletes probably allows for a reduction in flow velocity and thereby a reduction in kinetic energy.

Adult