Search

Background The latest research clearly indicates that diet plays an important role in the onset and course of inflammatory bowel diseases (IBD). But especially data on gender specific aspects of diet in IBD patients are still lacking even though we know from the general population that gender matters in case of diet. Methods We hypothesised an interaction of gender and diet in IBD patients and that this is linked to disease behaviour. In a subgroup analysis of a previously published prospective trial (Wiestler M. et al., Clinical and Translational Gastroenterology, 2019) 91 IBD patients were stratified into 4 groups (Crohn’s disease - CD [n=50] and ulcerative colitis – UC [n=41], female and male, respectively) to compare nutritional behaviour by sex and diagnosis. We evaluated disease-specific quality of life (IBDQ), physical activity (accelerometery), body composition (bioelectrical impedance analysis (BIA)), as well as clinical (HBI, SCCAI) and biochemical (CRP, faecal calprotectin) parameters of disease activity in comparison to nutritional behaviour (food frequency questionnaire (FFQ)). Results The nutritional behaviour of CD patients showed significant gender-related trends and differences in correlation with disease activity (Spearman correlation analysis). In male CD patients HBI significantly negatively correlated with the amount of fish (p=0.005, r=-0.612) and meat consumed per month (p=0.023, r=-0.519). In female CD patients the amount of fish consumed per month significantly negatively correlated with the IBDQ score (p=0.029, r=-0.438). The nutritional behaviour of UC patients showed significant gender-related trends and differences in correlation with disease activity as well. In female patients SCCAI significantly negatively correlated with the amount of cake, pie/ sweet baked goods (p= Conclusion In this subgroup analysis of a cross-sectional study, nutritional behaviour of IBD patients showed significant gender-related differences in correlation with disease activity and disease related quality of life. Due to the close correlation between IBD and nutrition and the different nutritional needs according to disease activity, our results illustrate the importance of gender-sensitive collection of a nutritional history as well as the need for gender-sensitive nutritional recommendations in IBD patients to further optimize individual patient care.

BackgroundTo examine the association between COVID-19 vaccination status and physical activity (PA), sporting behavior, as well as barriers to PA in adults in Switzerland, Germany, and Austria.MethodsA total of 1516 adults provided complete responses to our online questionnaire sent out in August 2021. Information about self-reported PA categories, sporting behavior, barriers to PA, and COVID-19 vaccination status were gathered. Main analyses were done using multiple linear regression adjusted for relevant parameters.ResultsWe found a significant association of vaccination status with total PA (p = .011), vigorous PA (p = .015), and moderate PA (p = .001) but not transport-related PA or sedentary time. Unvaccinated adults tended to have more total and vigorous PA than those vaccinated once (ratios of geometric means: 1.34 and 1.60, respectively) or twice (1.22 and 1.09, respectively). Yet, not sufficient evidence was available to confirm this. There was no between-group difference in the contribution of leisure time, work-related, or transport-related PA to total PA. Vaccination status was not associated with sporting behavior except for jogging as the primary intensive type of sports. Finally, there were no significant differences in any of the COVID-19 specific barriers to PA between groups.ConclusionOur data showed that vaccination status is associated with PA even in summer, where the number of COVID-19 cases was low and the severity of safety measures was mild. These findings may enhance future research and improve/extend COVID-19-specific PA guidelines.

The leading cause of morbidity and mortality in the world is ischemic heart disease. Physical activity is a major approach in prevention and therapy of cardiac diseases. Self-heart-rate-monitoring in daily life is an important point for health awareness of cardiac patients. Aim of this study was validation of measurement accuracy of seven different devices against ECG-monitoring during cardiac rehabilitation training on a bicycle ergometer. Tested devices were: Garmin Forerunner 35 (Garmin), Mio Fuse (Mio), Fitbit Charge HR (FitbitHR), Fitbit Surge (FitbitS), Withings Pulse™ Ox (Withings), Apple Watch Series 1 (Apple) and Pearl Fitness-Tracker (FBT-50.HR PRO.V4). All devices were tested on 35 participants with six timed measurements during 20 minutes constant load bicycle ergometer workout for each. Simultaneousely, ECG measurements were recorded. Pearson´s correlations were assessed. Apple, Mio, and Garmin showed excellent accuracy with close correlation to ECG for self-monitoring of heart rate (HR) during cycling. FitbitHR, Pearl and FitbitS presented reasonable results. In contrast, Withings showed poor correlation to ECG with significant differences. We found significant differences between the tested devices. Since accuracy is of major importance for cardiac patients, only Apple, Mio and Garmin could be recommended. However, further research within distinct clinical and non-clinical settings is necessary and should take different types of physical activities into account.

Blood flow restriction (BFR) limits arterial and venous blood flow and leads to blood pooling, which could increase exercise-induced training effects. Strength training at lower intensities (20-30% of maximum strength) in combination with BFR showed similar effects on muscle hypertrophy as training with 70% without BFR. Low-intensity cycling endurance training with BFR improves muscle hypertrophy and endurance performance and activates angiogenesis. After determination of the complete occlusion pressure on the corresponding extremity, it is recommended that BFR training should be performed with 40-80% of the measured occlusion pressure. During strength training of the upper extremities, an occlusion of 60-80% leads to a reduction in the arterial blood flow by 20-50%. Local ischemia and hypoxia, a stronger metabolic stimulus, swelling of the muscle cells and the increased oxidative stress are discussed as causes for the increased training effects due to BFR. In short-term studies, comparable adjustments to parameters of fibrinolytic activity, coagulation and inflammation could be observed for strength training with and without BFR. So far, thromboses after BFR have been described only rarely but need to be further clarified by appropriate studies. The BFR training leads to a stronger activation of the muscular metabolic reflex and thus to a relatively greater increase in exercise blood pressure, so that cardiovascular parameters should be controlled during BFR training. First meta-analyses with small numbers of healthy people and patients indicate the effectiveness of BFR training. Standardization or guidelines for clinical use are still lacking.

Ab dem 30. Lebensjahr sinkt die korperliche Leistungsfahigkeit pro Dekade um 5–20 %. Hohe physische Aktivitat im Alltag wie auch gezieltes Training von Ausdauer, Kraft, Koordination und Beweglichkeit konnen den (Funktions‑)Verlust von Muskeln, Knochen, Knorpel und Bindegewebe um mehr als 10 Jahre verzogern. In den letzten Jahren wurden fur zahlreiche Konzepte in der sportmedizinischen Therapie internistischer Erkrankungen wissenschaftliche Belege gefunden. Ahnlich wie bei der medikamentosen Behandlung sind nun zellulare Wirkmechanismen des Trainings im Detail bekannt. Mit diesen Kenntnissen konnen Art, Dosis und Intensitat des Trainings so definiert werden, dass die medizinische Trainingstherapie bei gezieltem Einsatz medikamentenahnliche Wirkungen erreicht. Dies gilt unter anderem fur Herz-Kreislauf-, Lungen-, Krebs- und Stoffwechselerkrankungen sowie fur das Immunsystem. In der Sporttherapie sollte ein individuelles Trainingsprogramm so definiert werden, dass die Inhalte Ausdauer, Kraft, Koordination und Beweglichkeit alle gesundheitlichen und personlichen Belange des Patienten adressieren. Fur nachhaltige Effekte und hohe Motivation des Patienten sind sowohl die individuelle und krankheitsspezifische Definition der Trainingsprogramme wie auch das regelmasige Abfragen der Durchfuhrung dieser Masnahmen erforderlich. Dabei helfen das „Rezept fur Bewegung“ oder die Verordnung von „Rehabilitationssport“ bzw. „Funktionstraining“.

After 30 years of age physical capacity decreases with increasing age by 5-20% per decade. High physical activity in daily life as well as exercise training of endurance, strength, coordination and mobility can delay the functional and anatomical loss of muscle, bone, cartilage and connective tissue by more than 10 years. In recent years, numerous concepts have scientifically been proven in the exercise therapy of internal diseases; therefore, similar to drug treatment, cellular mechanisms of exercise training adaptation are known in detail. With this knowledge the type, dose and intensity of exercise training can be defined in such a way that the targeted use of physical training can achieve health benefits similar to the effects achieved by drugs. This applies to the cardiovascular system, lungs, cancer, metabolic diseases and the immune system. In exercise training therapy of patients, individual exercise programs should be defined in a way that the contents of endurance, strength, coordination and mobility address all health and personal concerns of the patient. For sustained effects and high motivation, the individual and disease-specific definition of exercise programs as well as regular monitoring are necessary. The prescription for movement as well as the prescriptions for sports rehabilitation and functional training incorporate important assistance in this context.

Bei gesteigerten Uberlebensraten nach Herztransplantation (HTX) ist die subjektive Lebensqualitat und Leistungsfahigkeit im Langzeitverlauf reduziert, einhergehend mit erhohten kardiovaskularen Risikoparametern. Ziel der prospektiven Studie war die Entwicklung und Evaluierung eines Modells zur Phase III Rehabilitation Herztransplantierter im Langzeitverlauf, um in Erganzung zur etablierten medizinischen Nachsorge Lebensqualitat, Gesundheitsverhalten und Risikosituation zu verbessern. Bei 20 Patienten der Interventions- bzw. 12 Patienten der Kontrollgruppe (IG (KG)); 5,1±2,2 (4,5±2,3) Jahre nach HTX; Alter: 55±7 (54±8) Jahre; BMI: 28,3±1,0 (28,7±0,9) kg·m–2) wurde vor und nach der Intervention bzw. Kontrollphase jeweils eine Ergospirometrie durchgefuhrt, die subjektive Lebensqualitat mit dem PLC-Fragebogen sowie die kardialen Risikoparameter untersucht. Intervention: Die IG erhielt an 10 Tagen, verteilt uber 12 Monate psychologische und sportmedizinische Beratungen sowie Ergometerausdauertests. Auf der Basis der Testergebnisse wurde fur die IG ein fernuberwachtes Heimergometertraining jeden 2. Tag uber 30 min individuell gesteuert. Die Kontrollgruppe erhielt das etablierte Nachsorgeprogramm. Nach einem Jahr und 114±18 Heimtrainingseinheiten stieg die Ausdauerleistung in der IG bei unveranderter Herzfrequenz von 46±12 auf 66±16 W (+ 43%, p

Resistance training and to a lesser extent endurance training are capable of enhancing protein synthesis in skeletal muscle via various signaling pathways. Additionally, the expression of muscle fiber types responds to different regimes of training stimuli and immobilization as characterized by changes in myosin heavy chain isoforms (I--IIA--IIX). Eccentric resistance training has been shown to be highly efficient in inducing sarcomeric protein assembly in the longitudinal orientation of muscle cells. However, concentric contractions lead to a hypertrophic response (increased fiber diameter) in muscle which can still be activated in old age. The central signaling pathway to mediate the elevation of protein synthesis in response to training is the mTOR pathway, which is also stimulated by free amino acids. Moreover, adaptation to endurance training is mediated by the calcium-calcineurin-NFATc1 pathway which is strongly activated by the calcium transients involved in the muscle contraction process. High contraction frequency and long duration of training sessions are essential for activation and maintenance of fiber type I expression as well as for induction of transformation of type II into type I fibers. Endurance training sessions should therefore be longer than 30 min and dominated by periods of high frequency contractions. A further factor in the muscular response to training includes the recruitment and integration of satellite cells into muscle fibers. Satellite cells can respond to muscular stretch, activity and injury with increased proliferation and can later be integrated into muscle fibers. Therefore, new myonuclei are available to enhance mRNA synthesis and protein expression in muscle cells. New understanding of the cellular mechanisms of signal transduction in muscle in response to training, bed rest and ageing will help to optimize training and interventions in an ageing population.

A prospective, randomized rehabilitation program was initiated to improve physical exercise capacity and psychosocial functioning in patients after lung transplantation (LTx) and to evaluate long-term intervention effects on health-related quality of life (HRQoL). 44 consecutive patients were randomized to either intervention (IG; n=22) or control group (CG; n=22) and were followed with cardiopulmonary exercise testings and HRQoL measurements (SF-36) for 15±3 months after LTx. Patient characteristics did not differ concerning age (IG 47±11/CG 46±9), gender (female IG 9/CG 10), and pulmonary function (IG 2.4±0.9/CG 2.6±0.9l). IG patients received regular psychosocial support and performed a home-based supervised ergometer training program. A total of 2760 training sessions were performed without adverse events. Before intervention no significant differences occurred between IG and CG for HRQoL; neither differences in maximum exercise capacity (in watt) (IG: 68±23/CG: 70±17), nor significant differences in maximum oxygen consumption (in ml/min-1/kg-1) were seen between IG (17±3) and CG (20±5). Following intervention differences in HRQoL between IG and CG were identified for life satisfaction (p

Quality of life in lung transplant recipients (LTR) is reported to be comparable with that of the general population. However, previous studies have shown that exercise capacity was reduced to 30 - 40 % of normal values. The purpose of this study was to investigate the gap between good self-reported quality of life and reduced exercise capacity in LTR, to describe possible correlations and to compare the results with those of a control group (CG).27 LTR 208 +/- 67 days after bilateral lund transplantation (16 male, 11 female; age: 46 +/- 10 years; body mass index: 24 +/- 3 kg x m (- 2), FEV (1) % 75 +/- 27 %) and 30 controls (17 male 13 female; age 47 +/- 15 years; BMI: 26 +/- 4 kg x m (- 2), FEV (1) % 103 +/- 15 %) performed cardiopulmonary exercise testing and were interviewed with the standardized German "Quality of life profile for chronic disease" self-rating questionnaire.Significant differences were shown in objective exercise related variables (peak oxygen consumption: LTR 15.1 +/- 1.8, CG 34.5 +/- 9.1 ml x min (- 1) x kg (- 1); p0,01); peak workload: LTR 1.0 +/- 0.2; CG 2.4 +/- 1.0 W. kg (- 1); p0.01); percentage of predicted workload: LTR 44 +/- 12, CG 115 +/- 33 %; p0.01). The rating of subjective quality of life in physical, psychological and social domains of LTR did not differ from values of the CG or of the general population (n = 1143). The quality of life in the physical domain correlated significantly with peak exercise capacity (LTR r = 0.44, p0.05; CG r = 0.37; p0.05).Patients 7 months after lung transplantation described their physical, social and psychological quality of life as equally good as the healthy control group. However, peak exercise capacity and oxygen consumption were markedly reduced. To improve physical capacity in the range of daily activities, an exercise training program should be offered to patients after lung transplantation.

Longterm treatment after heart transplantation (HTX) improves survival, although the quality of life and exercise tolerance decreased continuously between one and ten years after transplantation. The role of physical exercise and psychological support in longterm treatment after HTX has not been determined. We analyzed the effects of a one year outpatient rehabilitation program in combination with a home based, computer assisted training program on exercise capacity, coronary risk factors and quality of life.20 heart transplant recipients in an intervention group and 12 patients after HTX in a control group participated in the study (IG (CG); 5.1+/-2.2 (4.5+/-2.3) years after HTX; age: 55+/-7 (54+/-8) years; body mass index: 28.3+/-1.0 (28.7+/-0.9) kg.m(-2)). Before and after the intervention, maximum and constant load exercise capacity, and self-reported quality of life were evaluated. The 12 month intervention period included 10 days of exercise testing as well as medical and psychological support. Furthermore, the IG group performed a computer-assisted and controlled home ergometer training every second day.After one year with 114+/-18 exercise training sessions, maximum oxygen consumption increased in the IG from 18.8+/-4.2 to 20.1+/-4.2 ml.min(-1).kg(-1) (p0.05; CG 19.3+/- 4.5 to 18.5+/-2.8 ml.min(- 1).kg(-1); p0.01 IG vs CG). In the IG, lower back pain, body fat, and blood pressure were all reduced, while the self-reported quality of life, endurance exercise capacity and HDL cholesterol were increased. No significant changes occurred in the control group.When initiated years after heart transplantation, longterm rehabilitation reduced coronary risk factors and significantly improved both the subjects' quality of life, as well as a near to normal capacity for physical work.

Exercise training for patients with coronary artery disease (CAD) is recommended in a wide range between 40-85% of maximum functional capacity (MFC) or 55-90% of maximum heart rate (HR). During exercise, high levels of catecholamines and metabolic acidosis could induce arrhythmia and ischemia. But catecholamines have never been determined in CAD during constant load exercise in the upper range of recommended intensities. In 11 CAD patients (age 58+/-8 years, BMI 26.1+/-4.0 kg x m(-2), NYHA I n=7, II n=4) we tested the maximum functional capacity (MFC), norepinephrine (NE), epinephrine (E) and blood lactate ([Lac(-)](B)) in a symptom-limited incremental ergometer test. Related to the exercise recommendation, the kinetics of NE, E and [Lac(-)](B) were determined in two 30 min constant load tests in randomized order: one was performed at the anaerobic lactate threshold (CTAT), a second was performed 10% above the individual threshold intensity (CT+10%). In the incremental tests maximum workload and VO(2) were 141+/-54 W and 1766+/-532 ml x min(-1), respectively (85+/-22% of normal; [Lac(-)](B) 5.7+/-1.9 mmol x l(-1), HR 138+/-28 b x min(-1), NE 11.7+/-5.1, E 1.6+/-1.4 nmol x l(-1)). In CTAT the anaerobic threshold (63+/-7% of MFC) represented the mean range of recommended exercise intensity for CAD (40-85%) and could be validated as steady-state intensity because catecholamines and [Lac(-)](B) concentrations remained constant after the initial increase (workload 88+/-35 W, [Lac(-)](B) 3.3+/-1.4 mmol x l(-1), HR 117+/- 23 b x min(-1), NE 8.3+/-3.5, E 0.8+/- 0.7 nmol x l(-1)). In all patients CT+10% (71+/-7% of MFC) led to a continuous rise in [Lac(-)](B), to a NE overload and to earlier exhaustion, although the intensities were in the recommended training range (workload 100+/-38 W, [Lac(-)](B) 5.8+/- 1.9 mmol x l(-1), HR 129+/- 29 b x min(-1), NE 13.9+/-6.9, E 1.5+/- 1.7 nmol x l(-1); p0.01 against CTAT for all except E). Conclusions In the upper range of recommended training intensity for CAD patients, norepinephrine and lactate were higher during endurance exercise than at MFC in incremental tests. Endurance exercise with intensities70% of MFC could overload the cardiac patient and increase the risk of arryhthmia and ischemia. Therefore, endurance exercise should be performed below 70% of MFC or below 85% of maximum HR, respectively, whereas higher intensities should apply to interval exercise.

Quality of life late after heart transplantation is reported to be comparable with that of the general population. However, peak exercise capacity remained approximately 60% of what was normal between 1 and 10 years after transplantation. The gap between patients' good quality of life and their impaired exercise tolerance is not yet explained. The purpose of our study was to examine the relation between quality of life and exercise- related variables in heart transplant recipients (HTR). Then, the results of these examinations were compared with those of patients having congestive heart failure (CHF), with the use of controls (C), respectively.(Mean values+/-SD) 29 HTR 4.4 +/- 2.1 years after transplantation, 29 CHF (NYHA II n = 22, III n = 7) and 29 C (age 54 +/- 9, 61 +/- 10, 56 +/- 10 years, body mass index 28 +/- 3, 29 +/- 5, 28 +/- 4 kg x m(-2), body fat 25 +/- 4, 27 +/- 6, 26 +/- 5%, respectively) performed cardiopulmonary exercise testing and were interviewed with the standardized German "Quality of life profile for chronic diseases" questionnaire.Peak oxygen consumption was impaired in HTR and in CHF compared with C (19.0 +/- 4.5, 18.6 +/- 4.3, and 30.2 +/- 6.6 ml x min x kg(-1), respectively; p0.01 vs. C each). HTR and CHF patients' quality of life in the physical scores were both impaired (p0.05 or p0.01 vs. C, respectively), but HTRs have reported better scores than CHF (p0.05). In the psychological role, CHF was impaired against C (p0.05), and HTR scores were comparable with C. In social functioning HTR and CHF patients both showed reduced quality of life dimensions. The Pearson correlation analysis showed that quality of life in physical functioning was related to peak oxygen consumption (p0.001) and percentage of predicted workload (p0.001). Quality of life in the social and psychological domains showed no association to exercise-related values.In HTR and in CHF, exercise testing variables were dominant predictors among the physical scales in quality of life, but not among social or psychological scales. Therefore, even late after heart transplantation, improving physical capacity should be a therapeutic goal with the intention of further increasing the quality of life.

Intensive physical exercise improves cardiac perfusion, skeletal muscle function and risk factors in patients with coronary artery disease (CAD). Otherwise, overdosed intensity can induce training adaptation as well as cardiac events. Therefore, we tested whether exercise intensity corresponding to an equilibrium between lactate production and elimination from the blood during incremental exercise tests represented the blood lactate [Lac-]B steady-state intensity during constant physical training. Randomized into two groups with 30 CAD patients each (T1: 25 male, 5 female; 59 +/- 7 years; T2: 26 male, 4 female; 60 +/- 9 years), the patients initially performed two successive incremental exercise tests. In the first test, workload was increased stepwise until exhaustion or symptom limitation (maximal workload: T1 142 +/- 48 watts, T2 145 +/- 45 watts) with the corresponding [Lac-]B accumulation of up to 6.7 +/- 2.6 (T1) or 6.5 +/- 2.0 (T2) mmol/l, respectively. After a seven minute active rest the second test began with 25 watts, increased with 5 (maximum workload in first test100 watts) or 10 watts per minute, respectively. During lower intensities in the second test, [Lac-]B initially decreased to an individual lactate minimum intensity (workload at LMI 83 +/- 32 in T1 or 86 +/- 29 in T2 watts, respectively; [Lac-]B at LMI 4.6 +/- 2.2 and 4.9 +/- 1.8 mmol/l, respectively) and then increased again. To check if the individual LMI represented the [Lac-]B steady-state workload in constant workload exercise, the patients performed 30 min constant load tests with the LMI (CT1) or a 30 min constant load test with an intensity 10% above the LMI (CT2), respectively. The workload in CT1 was 83 +/- 32 watts with a mean exercise time of 29.0 +/- 1.7 min. After 10 min of exercise the [Lac-]B steady state was reached at 3.3 +/- 1.4 mmol/l with no further increase in the last 20 min. The mean workload in CT2 was 95 +/- 31 watts with an exercise time of 23.3 +/- 8.3 min (p0.01). [Lac-]B increased from 4.4 +/- 1.7 mmol/l after 10 min to 4.7 +/- 2.0 mmol/l at the end (p0.01). Fifty percent of patients stopped CT2 before the 30 minute end. The results indicates that the LMI, estimated during lactic acidosis in two successive incremental tests, represented the individual lactate steady-state intensity also during constant load exercise. Therefore, training regimens for CAD patients could be deduced from LMI.

After acute hospital therapy of myocardial infarction or bypass surgery the patient in Germany will be treated using an inpatient rehabilitation programme for 3-4 weeks. One year later only 10% of them are still active in outpatients groups. In our study 61 cardiac patients performed an one-year outpatient rehabilitation (instead of 4 weeks inpatient) programme with intense supervised exercise and behaviour therapy. The money input per patient was the same for the usual care 4 weeks inpatient (6000 DM) as for 1 year outpatient rehabilitation (5800 DM). The exercise capacity per heart rate-blood pressure-product was increased by 43% (p0.01) after 12 months. The maximum exercise capacity was reached in the 57th week. Without increased medical treatment, cholesterol and LDL-cholesterol were reduced after 12 months by 3.9% down to 195 +/- 25 mg/dl or by 6.6% down to 122 +/- 21 mg/dl, respectively (n.s.). HDL-cholesterol increased by 2.8% to 48 +/- 8 mg/dl (n.s.). This study shows results similar to outpatient rehabilitation programmes in the United States or in Sweden. The long intervention time and the intensity are main factors for the success of cardiac rehabilitation and patient health. Financial resources should primarily be concentrated on long-term outpatient rehabilitation programmes.

In Germany cardiac rehabilitation contains a comprehensive 3 to 4 week inpatient program. The aim of our study was to perform an outpatient long-term rehabilitation including intense exercise and behavior therapy. In this setting the health benefits could be increased over the first 6 months. Hundred and twelve patients (94 men and 18 women, age 55 +/- 11 years) after myocardial infarction (52%), bypass-surgery (37%), PTCA (23%), and others (15%) were included in the ongoing study. Cholesterol and LDL-cholesterol diminished significantly. HDL-cholesterol was increased significantly after 6 months. The endurance exercise capacity per rate-pressure-product was increased by 46% during the 6 months period. The intake of cholesterol could significantly be diminished from 307 +/- 25 to 258 +/- 19 mg per day. Five of 16 patients became free from smoking. The first results from the long-term outpatient program show that the time of intervention and also the intensity of the medical, exercise and the behavior therapy are important factors for a successful rehabilitation.

During an incremental exercise test after a preceding bout of maximum exercise, blood lactate initially decreases to an individual minimum and then increases again. To determine whether this minimum represents an individual equilibrium between lactate production and catabolism during constant load exercise, the following field tests were performed: in 25 runners and five basketball players (series 1) the speed corresponding to the individual lactate minimum (LM) was measured in test 1 (incremental test after exercise induced lactic acidosis). On two occasions, two constant speed runs over 8 km were performed, one using the LM speed (LMS) (test 2), and another at a running speed of 0.2 m.s-1 above the LMS (test 3). Results of runners/basketball players: blood lactate concentration ([Lac-]B) in test 2 changed from 3.6/4.9 mmol.l-1 to 4.0/4.9 mmol.l-1 during the last 4.8 km, in test 3 from 4.6/4.6 mmol.l-1 to 6.5/6.9 mmol.l-1. These results indicate: 1) the LM speed in test 1 corresponds to a maximum lactate steady state speed during constant load exercise; 2) only a slight speed increase above the LM speed results in continuous marked [Lac-]B increase and earlier exhaustion. Variation of the increment duration in 13 males (series 2) shows no change of the LMS using 800-m and 1200-m increments (4.49 and 4.44 m.s-1) but a marked shift to higher speed using 400-m increments (4.96 m.s-1). Effects of low muscle glycogen stores on the LMS were determined in 10 males (series 3).(ABSTRACT TRUNCATED AT 250 WORDS)