Biomedical subjects

S Aunola

Publications and source records attributed to S Aunola.

At least 19 recordsLinked to original sources

PubMed2006

Effects of external light loading in power-type strength training on muscle power of the lower extremities in middle-aged subjects.

The purpose of this study was to evaluate and compare the effects of training either with a light load or without any load in a 16-week power-type strength training intervention in sedentary middle-aged subjects. A total of 85 subjects participated in the study. In a supervised 22-week training intervention, including 16 weeks of power-type strength training, 42 subjects (Light Load group=LL group) trained with a 1.1 kg weight on each ankle and 43 subjects (No Load group=NOL group) trained without any external load. Subjects were comparable concerning their training attendance, and anthropometric and physiological characteristics. Training effects were evaluated by measuring Vertical Squat Jump (VSJ), 20-metre Running Time (20 mRT), Maximal Anaerobic Cycling Power of leg muscles (MACP), and Maximal Oxygen Uptake (V.O (2 max)) before and after the intervention. The LL group improved VSJ and MACP significantly (p<0.05), compared with the NOL group. No difference between the groups was observed in 20 mRT or in V.O (2 max). To conclude, the external loads of 2.2 kg, in total, increased the efficiency of power-type strength training in vertical jumps and in anaerobic power in leg muscles, but not in sprint running.

Adult↗

PubMed2006

The profile and distribution of myosin heavy chain isoforms in middle-aged sedentary persons.

AIM: Human lifestyle has drastically changed during the past century as the share of physical work in daily life has decreased. The purpose of the present study was to examine the distribution of myosin heavy chain (MHC) isoforms in middle-aged sedentary persons, to compare the proportion of MHC isoforms of middle-aged and young sedentary persons and to demonstrate the effect of physical activity of MHC isoforms in middle-aged sedentary persons. METHODS: Eighty-nine middle-aged sedentary and 13 young sedentary persons volunteered for the study. Thirty middle-aged sedentary subjects participated in strength-conditional exercise program during 9 months. Vertical jumping height and maximal anaerobic work capacity were measured. Muscle samples were taken from vastus lateralis muscle. MHC isoform composition was determined by SDS-PAGE. RESULTS: Variation of MHC I and MHC IIa isoforms in middle-age sedentary persons demonstrated normal distribution. Significant differences of MHC isoform proportions between middle-aged and young sedentary participants were not observed. The proportion of MHC IIx decreased significantly after the exercise period that significantly improved the maximal anaerobic power and jumping height of participants. CONCLUSIONS: Normal distribution illustrated the proportion of MHC I and MHC IIa isoforms in 89 middle-aged sedentary persons while significant differences of MHC isoforms proportion between young and middle-aged sedentary persons were not observed. Even small increase of physical activity improved physical performance and decrease the MHC IIx proportion of middle-aged sedentary persons. Physically active lifestyle in middle age, when age-related changes have not started yet, may delay age-related changes in skeletal muscle.

Adult↗

PubMed2005

Improved fibrinolysis by an intensive lifestyle intervention in subjects with impaired glucose tolerance. The Finnish Diabetes Prevention Study.

AIMS/HYPOTHESIS: The aim of this study was to investigate the effects of lifestyle intervention on the levels of plasminogen activator inhibitor (PAI-1) and fibrinogen in subjects participating in the Finnish Diabetes Prevention Study (DPS). METHODS: In five DPS centres, 321 subjects with impaired glucose tolerance (intervention group, n=163; control group, n=158) had their PAI-1 and fibrinogen levels measured at baseline and at the 1-year follow-up. Additional 3-year follow-up assessments were carried out in a sample of 97 subjects in one of the DPS centres (Turku). The intervention programme included an intensive lifestyle intervention aiming at weight reduction, healthy diet and increased physical activity. RESULTS: During the first intervention year, PAI-1 decreased by 31% in the intervention group but showed no change in the control group (p<0.0001). In the Turku subgroup, the decrease in PAI-1 persisted throughout the 3-year follow-up. Changes in PAI-1 were associated with the number of lifestyle changes made during the first year (p=0.008). Weight reduction was the most important factor explaining the decrease in PAI-1. Changes in fibrinogen levels did not differ between the groups. CONCLUSIONS/INTERPRETATION: In addition to the previously reported reduction in the risk of type 2 diabetes in DPS participants with impaired glucose tolerance, the intensive dietary and exercise intervention had beneficial long-term effects on fibrinolysis as indicated by the reduced levels of PAI-1. These results suggest that elevated PAI-1 levels in obese subjects with impaired glucose tolerance are mostly reversible by lifestyle changes, especially those geared to weight reduction.

Adult↗

PubMed2005

Role of skeletal muscle-fibre type in regulation of glucose metabolism in middle-aged subjects with impaired glucose tolerance during a long-term exercise and dietary intervention.

AIM: The aim of this study was to investigate the role of skeletal muscle fibre type in the regulation of glucose metabolism in middle-aged obese subjects with impaired glucose tolerance (IGT) during a 2-year exercise and dietary intervention. METHODS: Muscle biopsies (musculus vastus lateralis) were taken from 22 subjects belonging to the intervention group of the Finnish Diabetes Prevention Study [1]. According to their myosin heavy chain (MHC) profile at the baseline, the subjects were divided into two groups: IGT(slow) (n=10) with a high proportion of MHC I isoforms and IGT(fast) (n=12) with a high proportion of MHC II isoforms in the vastus lateralis muscle. The intervention consisted of dietary counselling, strength and power training and/or aerobic exercise. The amount of exercise was the same in both groups; the exercise frequency was 5.1+/-2.7 h/week in the IGT(slow) and 5.1+/-2.8 h/week in the IGT(fast) group. RESULTS: Fasting glucose (p<0.05), 2-h glucose (p<0.05), fasting insulin (p<0.05), haemoglobin A1c (HbA(1c)) (p<0.01) and insulin resistance (p<0.05) [homeostasis model assessment for insulin resistance (HOMA-IR)] decreased in the IGT(fast) group, whereas only the 2-h glucose and HbA(1c) concentrations decreased in the IGT(slow) group. The amount of the glycogen synthase kinase-3-alphabeta (GSK-3-alphabeta) decreased in the IGT(fast) group (p<0.05). Exercise training increased the lactate dehydrogenase (LDH) (p<0.01), LDH-1 (p<0.05) and citrate synthase (CS) (p<0.05) activities in the vastus lateralis muscle in the IGT(slow) group, but only the CS activity (p<0.05) in the IGT(fast) group. CONCLUSIONS: The glucose metabolism improved both in the IGT(slow) and IGT(fast) group during the 2-year exercise and dietary intervention. The change was more prominent in the IGT(fast) group than in the IGT(slow) group, associated with the decrease of the GSK-alphabeta protein expression in skeletal muscle. The exercise training improved both glycolytic and oxidative capacity in the vastus lateralis muscle. The glycolytic capacity improved in the IGT(slow) group and the oxidative capacity in both groups.

Adult↗

PubMed2004

Effects of a 6-month exercise program on patients with multiple sclerosis: a randomized study.

OBJECTIVE: To improve walking and other aspects of physical function with a progressive 6-month exercise program in patients with multiple sclerosis (MS). METHODS: MS patients with mild to moderate disability (Expanded Disability Status Scale scores 1.0 to 5.5) were randomly assigned to an exercise or control group. The intervention consisted of strength and aerobic training initiated during 3-week inpatient rehabilitation and continued for 23 weeks at home. The groups were evaluated at baseline and at 6 months. The primary outcome was walking speed, measured by 7.62 m and 500 m walk tests. Secondary outcomes included lower extremity strength, upper extremity endurance and dexterity, peak oxygen uptake, and static balance. An intention-to-treat analysis was used. RESULTS: Ninety-one (96%) of the 95 patients entering the study completed it. Change between groups was significant in the 7.62 m (p = 0.04) and 500 m walk tests (p = 0.01). In the 7.62 m walk test, 22% of the exercising patients showed clinically meaningful improvements. The exercise group also showed increased upper extremity endurance as compared to controls. No other noteworthy exercise-induced changes were observed. Exercise adherence varied considerably among the exercisers. CONCLUSIONS: Walking speed improved in this randomized study. The results confirm that exercise is safe for multiple sclerosis patients and should be recommended for those with mild to moderate disability.

Adult↗

PubMed2004

Exercise capacity, disability and leisure physical activity of subjects with multiple sclerosis.

The purpose of the present study was to examine exercise capacity and its relationship to neurological disability as measured using the Expanded Disability Status Scale (EDSS) and to leisure physical activity in subjects with multiple sclerosis (MS). Thirty-four men and 61 women (mean age 44 +/- 6.7 years, mean disease duration 5.7 +/- 6.4 years) with mild to moderate disability (EDSS range 1.0-5.5) participated. They underwent an incremental exercise test on a leg cycling ergometer. Leisure physical activity was measured using a questionnaire. Peak oxygen uptake (VO2peak) in men was 27.0 +/- 5.2 mL/kg/min, and in women 21.7 +/- 5.5 mL/kg/min. The disability correlated inversely with the VO2peak both in men (r = - 0.50, P = 0.004) and in women (r = - 0.25, P = 0.05). No correlation between disease duration and VO2peak was found. In a multivariate regression analysis, neurological disability was confirmed as a predictor of VO2peak. No evidence of a relationship between leisure physical activity and VO2peak was found. A main finding was that disability and exercise capacity are inter-related, even in subjects who are not severely handicapped (84% had an EDSS of < 4.0). The level of disability should be taken into account in the planning of aerobic exercise programs for fully ambulatory MS subjects.

Adult↗

PubMed2003

Feasibility of power-type strength training for middle aged men and women: self perception, musculoskeletal symptoms, and injury rates.

OBJECTIVES: To examine the feasibility of a power-type strength training programme for middle aged men and women, the impact of the training programme on perceived health and fitness and on knee and low back symptoms, and the rate of exercise induced injuries. METHODS: A total of 154 voluntary, healthy, sedentary men and women participated in a training programme lasting about four months. The explosive force of leg extensor muscles was measured by means of standing long jumps and vertical squat jumps. Perceived health, perceived fitness, and low back and knee symptoms were assessed before and after the intervention by using a questionnaire. Musculoskeletal disorders and exercise induced injuries were reported during the training programme. RESULTS: Perceived fitness improved in both men (p<0.01) and women (p<0.0001), but perceived health only in women (p<0.01). Men with increased explosive force in squat jumping also showed better perceived health (p<0.05), and women with increased explosive force in standing long jump showed better perceived fitness (p<0.05). Exercising men who had increased knee symptoms had significantly higher body mass index than the other exercising men (p<0.05). The exercise induced injury rate was 19% in men and 6% in women. CONCLUSIONS: Successful completion of the exercise programme, together with the increased physical activity and relatively low injury rate, may have contributed to the participants finding the exercise programme positive and stimulating and believing that their health and fitness had improved. The low rate of musculoskeletal injury suggests that this type of supervised exercise programme is feasible for untrained middle aged people.

Adult↗

PubMed2002

Visceral fat and psychosocial stress in identical twins discordant for obesity.

OBJECTIVES: Accumulation of intra-abdominal fat has been suggested, but not yet proved, to be basically as a result of chronic psychosocial stress causing arousal of hypothalamic-pituitary-adrenal cortex axis. Our objectives were to study the association between psychosocial stress, obesity and body fat distribution when genetic factors are identical. DESIGN: Monozygotic twins discordant for obesity were examined in an in-patient setting. SUBJECTS: Adult monozygotic twin pairs (12 female, 8 male) with an average intrapair difference of 17 kg in body weight. They were divided into two groups: in group A the visceral fat area of the obese cotwin was higher and, in group B, lower than the gender-specific median value. MAIN MEASURES: Hormonal, physiological and psychological distress indicators, and sleep measures. RESULTS: Daily urinary cortisol and noradrenaline excretion were higher in the obese cotwins when compared with the nonobese cotwins in group A but not in group B (P=0.026 and 0.020 when intrapair differences were compared between groups A and B, respectively). In serum cortisol, ACTH and CBG concentrations a similar trend was not statistically significant. In group A, the obese cotwins consumed almost 2.5 times as much alcohol as their lean cotwins, whilst in group B the situation was the opposite. The mean amount of active sleep was significantly higher and that of quiet sleep significantly lower in the obese than the lean cotwins only in group A. Intrapair differences in emotional reactions indicating distress and lack of subjective energy were seen only in group A. CONCLUSION: When genetic factors are identical, visceral fat accumulation, rather than obesity in general, is associated with increased psychosocial stress and concomitant hormonal changes.

Adipose Tissue↗

PubMed2001

Isoresistive dynamometer measurement of trunk muscle velocity at different angular phases of flexion and extension.

Isoresistive trunk muscle dynamometer is a potentially useful piece of equipment in evaluation of trunk muscle velocity, but to date, studies analysing the possibilities and limitations of such measurements are scarce. The aim of this study was to analyse the trunk muscle velocity in repetitive flexion and extension movements at three different angular phases, using an isoresistive trunk muscle dynamometer, and to assess the reliability of the measurements. The study population consisted of 120 healthy, sedentary men and women who volunteered for the study. The measurements were carried out before and after a 22-week training intervention programme. The results show that the peak velocities of the phases between 15 and 35 degrees in flexion and 20-0 degrees in extension (i.e. the second phases) correlated highly (r=0.99 in flexion and in extension) with the peak velocity of the whole movement ranging from -5 to 55 degrees in flexion and 40 to -20 degrees in extension. Correlations were high, both before and after the intervention. The LISREL model analysis showed high reliability of measurement for the second angular phases (in flexion and extension). According to the model, the correlation between the first and second measurement (with a 22-week training intervention in between) was 0.78 in flexion and 0.81 in extension. In conclusion, the angular phases from 15 to 35 degrees in flexion and from 20 to 0 degrees in extension represent the peak velocity of the whole movement. Negative residual correlations between the first and last angular phases in the LISREL model reflect the way of performing the movement: the faster the start the slower the end, and vice versa.

Adult↗

PubMed1999

Prevention of Type II diabetes in subjects with impaired glucose tolerance: the Diabetes Prevention Study (DPS) in Finland. Study design and 1-year interim report on the feasibility of the lifestyle intervention programme.

UNLABELLED: AIMS/HYPOTHESIS; The aim of the Diabetes Prevention Study is to assess the efficacy of an intensive diet-exercise programme in preventing or delaying Type II (non-insulin-dependent) diabetes mellitus in subjects with impaired glucose tolerance, to evaluate the effects of the intervention programme on cardiovascular risk factors and to assess the determinants for the progression to diabetes in persons with impaired glucose tolerance. METHODS: A total of 523 overweight subjects with impaired glucose tolerance ascertained by two oral glucose tolerance tests were randomised to either a control or intervention group. The control subjects received general information at the start of the trial about the lifestyle changes necessary to prevent diabetes and about annual follow-up visits. The intervention subjects had seven sessions with a nutritionist during the first year and a visit every 3 months thereafter aimed at reducing weight, the intake of saturated fat and increasing the intake of dietary fibre. Intervention subjects were also guided individually to increase their physical activity. RESULTS: During the first year, weight loss in the first 212 study subjects was 4.7 +/- 5.5 vs 0.9 +/- 4.1 kg in the intervention and control group, respectively (p < 0.001). The plasma glucose concentrations (fasting: 5.9 +/- 0.7 vs 6.4 +/- 0.8 mmol/l, p < 0.001; and 2-h 7.8 +/- 1.8 vs 8.5 +/- 2.3 mmol/l, p < 0.05) were significantly lower in the intervention group after the first year of intervention. Favourable changes were also found in blood pressure, serum lipids and anthropometric indices in the intervention group. CONCLUSION/INTERPRETATION: The interim results show the efficacy and feasibility of the lifestyle intervention programme.

Blood Glucose↗

PubMed1996

Sleep in monozygotic twin pairs discordant for obesity.

Nocturnal motor breathing and cardiac activity were recorded by using the static charge-sensitive bed, and sleep habits were studied by questionnaire in 24 pairs of monozygotic twins discordant for their body mass index; the mean intrapair difference between co-twins was 6.7 kg/m2. Intrapair differences in sleep characteristics between co-twins were related to intrapair differences in physiological and anthropometric characteristics. Two questions were tested. First, do monozygotic twins discordant for body mass index differ in sleep behavior? Second, if they do, are differences in sleep associated with nongenetic differences in the body weight and metabolism or with other environmental factors? Obese twins had higher nocturnal motor activity levels, less quiet sleep, and more habitual snoring than did their nonobese co-twins. Differences in sleep were associated with obesity-related factors. However, habitual snoring did not explain other intrapair differences in sleep. It was concluded that relatively moderate obesity is associated with disruption of physiological structure of sleep as measured by the static charge-sensitive bed method and that this disruption seems not to be associated with snoring or breathing disturbances.

Adipose Tissue↗

PubMed1992

Does anaerobic threshold correlate with maximal lactate steady-state?

The aim of this study was to compare the 'anaerobic threshold' (AnT) of subjects determined during a continuous 2-min incremental exercise test until exhaustion and the 'maximal lactate steady-state' (BLaSsmax) determined during prolonged exercise at constant loads corresponding to the subjects' AnT and/or 5-25% above and below it. Seventeen subjects performed an incremental exercise test and 1-5 prolonged exercise tests on a cycle ergometer until exhaustion at intervals of 1 week, and work rates, oxygen uptake (VO2) values and brachial venous blood lactate (BLa) levels were measured. It was proposed that when exercising at a constant workload below AnT, BLa would fall after having reached its peak; at the level of AnT, BLa reaches maximal steady-state (BLaSsmax); and above AnT, BLa increases continuously. Altogether, in 34 of 45 tests with a constant workload between 80 and 125% AnT, BLa values were as expected. In those cases in which BLaSsmax was reached, BLa increased on average by 3.8 mM from resting levels. This increase was 2.0 mM greater than that seen between resting levels and AnT during incremental exercise. There was no correlation between BLa values at BLaSsmax and at AnT, both when expressed as an increase in BLa (delta BLa) and absolute BLa concentration. Altogether, 81% of the variation in BLa concentration at BLaSsmax could be explained by the subjects' age, the percentage of slow-twitch fibres and BLa levels at rest. The AnT and BLaSsmax did not differ significantly, and these values were correlated (r = 0.83). Together, AnT and age accounted for 85% of the variation seen in BLaSsmax. The BLaSsmax did not correlate with AnT when fixed at a BLa concentration of 4 mM (AnT4mM). The three hypotheses tested in this study were confirmed, and the present results demonstrate that AnT correlates with BLaSsmax. The few exceptions to anticipated BLa kinetics were small in magnitude and could be explained by physiological variations.

Adenosine Triphosphatases↗

PubMed1990

The relation between cycling time to exhaustion and anaerobic threshold.

This study investigated whether the anaerobic threshold (AnT) could be used to predict prolonged work capacity measured as cycling time to exhaustion (= endurance time) and which factors, in addition to relative exercise intensity, could explain variation in endurance time. Theoretical exercise intensities corresponding to certain endurance times were also calculated. The hyperbolic and exponential functions between cycling time and relative work rate (WR[%]), as well as between cycling time and relative oxygen uptake (VO2[%]) were fitted to the pooled data (n = 45) of 17 subjects. The WR(%) and VO2(%) were expressed as a percentage of the subject's own AnT- and maximum-values. At WR corresponding to AnT (i.e., 70% of WRmax) an average subject could cycle 60 min according to both AnT- or maximum-related exponential function. When prediction was done for an endurance time of 4 h, the AnT-related exponential function gave 2.9%-units (= 11 W or approximately 0.15 O2 l.min-1) lower intensity level (51% of WRmax) than the maximum-related function (54% of WRmax). The WR(%) alone explained 54% and 70% of the variation in endurance time of the AnT-related and maximum-related exponential functions, respectively. Muscle fibre composition and initial blood lactate or relative muscle glycogen depletion (change in muscle glycogen as percentage) increased significantly the explanatory power of these models. The differences between the observed and expected exercise times correlated with blood lactate accumulation (r = -0.42; p less than 0.01), muscle fibre composition (r = 0.33; p less than 0.05) and relative muscle glycogen depletion (r = 0.67; p less than 0.01). It was concluded that the capacity for prolonged work measured as cycling time to exhaustion can be estimated by AnT-related power output, and that the exponential function model is the most suitable. Prediction power of the model can be improved by multiple regressions including muscle fibre composition, initial blood lactate level and relative muscle glycogen depletion.

Adult↗

PubMed1988

Comparison of two methods for aerobic threshold determination.

A new method of aerobic threshold (AerT) determination, as a minimum of so-called lactate equivalent (Berg et al. 1980; Lehmann et al. 1983), was compared with the generally used method (AerT1) presented first by Wasserman et al. (1973). The comparison was made with data from 32 subjects in repeated maximal exercise tests on a bicycle ergometer. The AerT as a minimum of lactate equivalent was determined using both a computerized method for curve fitting (AerT3) and visual inspection (AerT2). AerT2 and AerT3 showed similarity: the regression coefficient was 0.88 and 0.95 and the correlation coefficient was 0.84 and 0.88 in the first and in the second tests, respectively. AerT1 and AerT2 showed similar mean estimated values, but AerT3 showed slightly higher mean values than AerT1 (p less than 0.05 and p less than 0.01) or AerT2 (p less than 0.01). The regression coefficients between AerT1 and AerT2 or AerT3 (0.60-0.71) showed different slopes from the identity (p less than 0.001). The corresponding correlation coefficients were 0.88 and 0.89 with AerT2, and 0.75 and 0.79 with AerT3 respectively in the first and second tests. However, in two thirds of all determinations the difference between these two estimation methods (AerT1 and AerT2) was less than or equal to 0.10 l O2.min-1. In conclusion, AerT as a minimum of lactate equivalent differed slightly from AerT determined using the traditional method. However, its determination criterion is unambiguous and allows objective computerized curve fitting. The physiological correlates of this new AerT index should be studied carefully before final evaluation of its usefulness in applications can be made.

Adult↗

PubMed1988

Muscle metabolic profile and oxygen transport capacity as determinants of aerobic and anaerobic thresholds.

Aerobic and anaerobic thresholds determined by different methods in repeated exercise tests were correlated with cardiorespiratory variables and variables of muscle metabolic profile in 33 men aged 20-50 years. Aerobic threshold was determined from blood lactate, ventilation, and respiratory gas exchange by two methods (AerT1 and AerT2) and anaerobic threshold from venous lactate (AnTLa), from ventilation and gas exchange (AnTr) and by using the criterion of 4 mmol.1(-1) of venous lactate (AnT4mmol). In addition to ordinary correlative analyses, applications of LISREL models were used. The 8 explanatory variables chosen for the regression analyses were height, relative heart volume, relative diffusing capacity of the lung, muscle fiber composition, citrate synthase (CS) and succinate dehydrogenase activities, the lactate dehydrogenase--CS ratio, and age. They explained 58% of the variation in AerT1, 73.5% that of AerT2, 71% that of AnTr, 74.5% that of AnTLa, and 67.5% that of AnT4mmol.AerT and AnT alone explained 77% of the variation in each other. Both AerT and AnT were determined mainly by a muscle metabolic profile, with the CS activity of vastus lateralis as the strongest determinant. The factor 'submaximal endurance' which was measured with AerT and AnT seemed to be slightly more closely connected to 'muscle metabolic profile' than was 'maximal aerobic power' (= VO2max), but both also correlated strongly with each other (r = 0.92).

Adult↗

PubMed1986

Psychoendocrine responses to bicycle exercise in healthy men in good physical condition.

Blood levels of cortisol, prolactin, somatotropin, dopamine, noradrenaline, adrenaline, and lactate were analyzed in 18 healthy men in good physical condition in four repeated bicycle exercise tests. Profiles of pituitary hormone secretion into blood varied intra- and interindividually from one test to another, even though the work load remained unchanged. Catecholamine and lactate levels regularly increased during each exercise test. A factor analysis of the endocrine responses supports the assumption that pituitary hormones respond to psychological state factors while catecholamines and lactate increases are related to physical load.

Adult↗

PubMed1986

Aerobic and anaerobic thresholds determined from venous lactate or from ventilation and gas exchange in relation to muscle fiber composition.

The aerobic and anaerobic thresholds determined from venous lactate (AerTLa and AnTLa) or from ventilation and gas exchange (AerTr and AnTr) in relation to muscle fiber composition were compared. Twelve subjects were studied in double exercise tests carried out until voluntary exhaustion. They were divided into two groups according to their muscle fiber type in the vastus lateralis muscle: ST group with a majority of slow-twitch fibers (ST% = 66.0% +/- 7.3%) and FT group with a majority of fast-twitch fibers (ST% = 27.7% +/- 8.4%). A 2-min incremental exercise test protocol on a bicycle was used. There were no significant differences between the ST and FT groups in the VO2max or in the Lamax. Neither the AerT nor the AnT related to the VO2max (%) differed between the ST and FT groups. In the FT group the AnTLa occurred 0.70 min in the first test and 1.06 min in the second test earlier than the AnTr, whereas in the ST group the AnTLa occurred at the same time or 0.44 min later, respectively, than the AnTr (P less than 0.05). Expressed as VO2 the differences between thresholds were not so distinct. The results demonstrated that the mutual relation between the AnTLa and AnTr seemed to be dependent on the fiber type majority in exercising muscles (vastus lateralis) among untrained men.

Adult↗

PubMed1984

Reproducibility of aerobic and anaerobic thresholds in 20-50 year old men.

The reproducibility of the aerobic (AerT) and the anaerobic (AnT) threshold was studied in 33 men aged 20-50 years. They completed two maximal exercise tests on a bicycle ergometer. The thresholds, as VO2 (1 X min-1), were determined visually by two investigators using both the blood lactate and the respiratory indices. The respiratory variables were measured with a computerized breath-by-breath method; samples of venous blood were drawn every 2nd min and analysed enzymatically for lactate. The reproducibility of the AerT (r = 0.94) and of the AnT (r = 0.96) were equally good. The AnT can be determined either from blood lactate concentrations (AnTLa) or from ventilatory and gas exchange response (AnTr) during a 2-min incremental exercise test. They both also showed similar reproducibility: r = 0.93 for the AnTLa and r = 0.95 for the AnTr. The work rate and the measured physiological variables at the AerT and AnT, except for the blood lactacte concentration, were very reproducible. Age did not affect the reproducibility of the thresholds. The poor reproducibility of blood lactate concentration of the AnT confirmed our previous opinion that the fixed blood lactate levels of 2 and 4 mmol X 1(-1) are poor indicators of AerT and AnT.

Adult↗