Rüdiger Reer

Impact of aerobic training on immune-endocrine parameters, neurotrophic factors, quality of life and coordinative function in multiple sclerosis

In recent years it has become clear that multiple sclerosis (MS) patients benefit from physical exercise as performed in aerobic training but little is known about the effect on functional domains and physiological factors mediating these effects. We studied immunological, endocrine and neurotrophic factors as well as coordinative function and quality of life during an 8-week aerobic bicycle training in a waitlist control design. In the immune-endocrine study (1) 28 patients were included, the coordinative extension study (2) included 39 patients. Training was performed at 60% VO(2)max after determining individual exertion levels through step-by-step ergometry. Metabolic (lactate), endocrine (cortisol, adrendocortico-releasing hormone, epinephrine, norepinephrine), immune (IL-6, soluble IL-6 receptor), and neurotrophic (brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF)) parameters were compared from a prestudy and a poststudy endurance test at 60% VO(2)max for 30 min. In study (1), lowered lactate levels despite higher workload levels indicated a training effect. Disease-specific quality of life (as measured by the Hamburg Quality of Life Questionnaire for Multiple Sclerosis, HAQUAMS) significantly increased in the training group. No significant training effects were seen for endocrine and immune parameters or neurotrophins. In study (2), two out of three coordinative parameters of the lower extremities were significantly improved. In summary, low-level aerobic training in MS improves not only quality of life but also coordinative function and physical fitness.

Basal serum levels and reactivity of nerve growth factor and brain-derived neurotrophic factor to standardized acute exercise in multiple sclerosis and controls

Neurotrophins like brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are thought to play an important role in neuronal repair and plasticity. Recent experimental evidence suggests neuroprotective effects of these proteins in multiple sclerosis (MS). We investigated the response of serum NGF and BDNF concentrations to standardized acute exercise in MS patients and controls. Basal NGF levels were significantly elevated in MS. Thirty minutes of moderate exercise significantly induced BDNF production in MS patients and controls, but no differential effects were seen. We conclude that moderate exercise can be used to induce neutrophin production in humans. This may mediate beneficial effects of physical exercise in MS reported recently.

Endocrine and cytokine responses to standardized physical stress in multiple sclerosis

Since the earliest descriptions psychological and physical stress has been considered a controversial but potentially important factor in the onset and course of multiple sclerosis (MS). During recent years it has become clear that MS patients benefit from physical exercise as performed in aerobic training. As acute exercise has profound effects on immune and endocrine parameters we studied endocrine and immune response to standardized physical stress in MS within a study of aerobic training. Fifteen MS patients completed an eight-week aerobic training program, 13 patients were part of a wait-control group. Twenty healthy controls were recruited as well. A step-by-step bicycle ergometry was performed to determine individual exertion levels. For the endurance test patients exercised at 60% VO2 max for 30 min. Blood samples were drawn before, directly after and 30 min after completion of the exercise. Heart rate and lactate increased in all groups (p<.0001). We furthermore saw significant increases in endocrine parameters (epinephrine, norepinephrine, ACTH, and beta-endorphin; all p<.0001) in healthy individuals and in MS patients but without a differential effect. Whole-blood stimulated production of IFN-gamma (IFNgamma) was induced similarly in all groups (p<.01). TNF-alpha (TNFalpha) and IL-10 were less inducible in MS patients (trend). From these data we could not demonstrate a proinflammatory immune deviation in response to physical stress in MS. The observed trend of hyporesponsive TNFalpha and IL-10 responses in MS warrants further investigation.

Differential cognitive effects of cycling versus stretching/coordination training in middle-aged adults.

OBJECTIVE Physical exercise has been linked to higher cognitive functioning and enhanced brain plasticity in aging humans. The most consistent positive effects have been reported for executive functions associated with frontal brain regions. In rodents, however, running has been shown to induce functional and structural changes in the hippocampus, a brain region known to be important for memory. It is still a matter of debate which cognitive functions are susceptible to exercise and whether an increase in cardiovascular fitness is beneficial for cognitive functioning. Moreover, little is known about the impact of exercise on cognition in middle-aged humans. METHOD Sixty-eight sedentary men and women between 40 and 56 years of age were randomly assigned to one of two training programs: aerobic endurance training (cycling) or nonendurance training (stretching/coordination). Both groups exercised twice a week for six months. Additionally, a sedentary control group was tested. At baseline and after six months, episodic memory, perceptual speed, executive functions, and spatial reasoning were assessed with standardized psychometric tests, and all participants underwent a cardiovascular fitness test. RESULTS Significant improvements in memory were observed in both the cycling and the stretching/coordination group as compared with the sedentary control group. The improvement in episodic memory correlated positively with the increase in cardiovascular fitness. The stretching/coordination training particularly improved selective attention as compared with the cycling training. CONCLUSIONS The results suggest that cardiovascular fitness has beneficial effects even in high-functioning middle-aged participants, but that these benefits are very specific to memory functions rather than a wider range of cognitive functions.

1-Set vs. 3-Set Resistance Training: A Crossover Study

This crossover study was conducted to investigate the effects of a 1-set and 3-set strength training program. The subjects were untrained men and women who were randomly signed into 1 of 3 groups: 10 subjects trained during the first 9 weeks (training period 1) with 1 set and 8–12 repetitions per set. After the break (9 weeks), they trained with 3 sets and 8–12 repetitions in training period 2. Twelve subjects started with the 3-set program and continued with the 1-set regime after the break. The control group (n = 7) did not train. The subjects were tested on 1 repetition maximum (1RM) for the biceps curl, leg press (unilateral: left and right), and bench press. Analysis of the data was done in a sampled manner for each strength training program (1-set and 3-set). The 1-set (n = 22) and 3-set (n = 22) programs led to significantly (p < 0.05) improved 1RM performances in every exercise. The relative improvements (%) for the 1RM were significantly higher during the 3-set program for the biceps curl and the bench press compared with the 1-set program. The control group exhibited no changes in any of the tested parameters over the course of this study. The design of this study allowed insight into the effects of different strength training volume without any genetical variations. The same subjects improved their 1RM during the 3-set program by 2.3 kg (biceps curl; corresponding effect size = 0.24), 8.9 kg (leg press right; 0.30), 10.9 kg (leg press left; 0.28), and 2.5 kg (bench press; 0.09) more than during the 1-set program. Depending on the goals of each trainee, these differences between the effects of different strength training volumes indicate that it may be worth spending more time on working out with a 3-set strength training regime.

Comparison of minimalist footwear strategies for simulating barefoot running: a randomized crossover study.

Possible benefits of barefoot running have been widely discussed in recent years. Uncertainty exists about which footwear strategy adequately simulates barefoot running kinematics. The objective of this study was to investigate the effects of athletic footwear with different minimalist strategies on running kinematics. Thirty-five distance runners (22 males, 13 females, 27.9 ± 6.2 years, 179.2 ± 8.4 cm, 73.4 ± 12.1 kg, 24.9 ± 10.9 km.week-1) performed a treadmill protocol at three running velocities (2.22, 2.78 and 3.33 m.s-1) using four footwear conditions: barefoot, uncushioned minimalist shoes, cushioned minimalist shoes, and standard running shoes. 3D kinematic analysis was performed to determine ankle and knee angles at initial foot-ground contact, rate of rear-foot strikes, stride frequency and step length. Ankle angle at foot strike, step length and stride frequency were significantly influenced by footwear conditions (p<0.001) at all running velocities. Posthoc pairwise comparisons showed significant differences (p<0.001) between running barefoot and all shod situations as well as between the uncushioned minimalistic shoe and both cushioned shoe conditions. The rate of rear-foot strikes was lowest during barefoot running (58.6% at 3.33 m.s-1), followed by running with uncushioned minimalist shoes (62.9%), cushioned minimalist (88.6%) and standard shoes (94.3%). Aside from showing the influence of shod conditions on running kinematics, this study helps to elucidate differences between footwear marked as minimalist shoes and their ability to mimic barefoot running adequately. These findings have implications on the use of footwear applied in future research debating the topic of barefoot or minimalist shoe running.

Wirbelsäulenform- und Funktionsprofile

BACKGROUND Functional diagnostic approaches are helpful in the treatment of low back pain (LBP) patients. Reference data of asymptomatic individuals might be helpful to understand individual case profiles of LBP patients, to derive movement therapy goals and issues and to improve quality management in therapy monitoring. METHODS Spinal form and mobility in the dorsal flexion (static and dynamic rasterstereography), as well as isometric peak forces (back extension/trunk flexion) were analyzed in a cross-sectional study of 103 pain-free volunteers (52 females, 51 males) aged 18-40 years. RESULTS Reference data could be demonstrated based on percentiles (5-95 %). There were significant differences between males and females for strength values and spinal form parameters describing the lumbosacral transition (p < 0.001), but not for the strength extension/flexion ratio (Ex/Flex), lumbar mobility (dorsiflexion) or any other spine shape parameter. CONCLUSION Despite the problem of a normal spinal alignment it is proposed to use reference data percentiles of asymptomatic persons to construct a musculoskeletal functional profile for individual LBP patients, which might emphasize the character of different LBP disorders and could be useful in screening, therapy planning and monitoring.

[Spinal form and function profile: reference values for clinical use in low back pain].

BACKGROUND Functional diagnostic approaches are helpful in the treatment of low back pain (LBP) patients. Reference data of asymptomatic individuals might be helpful to understand individual case profiles of LBP patients, to derive movement therapy goals and issues and to improve quality management in therapy monitoring. METHODS Spinal form and mobility in the dorsal flexion (static and dynamic rasterstereography), as well as isometric peak forces (back extension/trunk flexion) were analyzed in a cross-sectional study of 103 pain-free volunteers (52 females, 51 males) aged 18-40 years. RESULTS Reference data could be demonstrated based on percentiles (5-95 %). There were significant differences between males and females for strength values and spinal form parameters describing the lumbosacral transition (p < 0.001), but not for the strength extension/flexion ratio (Ex/Flex), lumbar mobility (dorsiflexion) or any other spine shape parameter. CONCLUSION Despite the problem of a normal spinal alignment it is proposed to use reference data percentiles of asymptomatic persons to construct a musculoskeletal functional profile for individual LBP patients, which might emphasize the character of different LBP disorders and could be useful in screening, therapy planning and monitoring.

Wirbelsäulenform- und Funktionsprofile@@@Spinal form and function profile: Referenzwerte für die klinische Nutzung bei Rückenschmerzsyndromen@@@Reference values for clinical use in low back pain

BACKGROUND Functional diagnostic approaches are helpful in the treatment of low back pain (LBP) patients. Reference data of asymptomatic individuals might be helpful to understand individual case profiles of LBP patients, to derive movement therapy goals and issues and to improve quality management in therapy monitoring. METHODS Spinal form and mobility in the dorsal flexion (static and dynamic rasterstereography), as well as isometric peak forces (back extension/trunk flexion) were analyzed in a cross-sectional study of 103 pain-free volunteers (52 females, 51 males) aged 18-40 years. RESULTS Reference data could be demonstrated based on percentiles (5-95 %). There were significant differences between males and females for strength values and spinal form parameters describing the lumbosacral transition (p < 0.001), but not for the strength extension/flexion ratio (Ex/Flex), lumbar mobility (dorsiflexion) or any other spine shape parameter. CONCLUSION Despite the problem of a normal spinal alignment it is proposed to use reference data percentiles of asymptomatic persons to construct a musculoskeletal functional profile for individual LBP patients, which might emphasize the character of different LBP disorders and could be useful in screening, therapy planning and monitoring.

FREIZEIT- UND FITNESSSPORT

Zusammenfassung Die Bestimmung der Milchsaurekonzentration (Laktat) im Blut bei definierten korperlichen Belastungsintensitaten mit Dokumentation der Herzfrequenz ist ein fester Bestandteil jeder Leistungsdiagnostik, sowohl im Leistungssport als auch fur den gesundheitlich orientierten Freizeit- und Fitnesssportler. Aus der Beziehung zwischen Laktatleistungskurve und Herzfrequenzverlauf konnen die fur verschiedene Trainingszustande individuell gunstigsten Herzfrequenzen zur Belastungssteuerung im Trainingsalltag (z.B. Grundlagenausdauer oder Fettstoffwechseltraining) abgeleitet werden. Ziel der Leistungsdiagnostik ist die Bestimmung der individuellen aerob-anaeroben Schwelle (IAAS). Vor dem Hintergrund der leistungsphysiologischen Zusammenhange sind jedoch bei der Durchfuhrung und Bewertung dieses Tests die wichtigsten Faktoren der Laktatbildung und -elimination zu beachten.