Christian Puta

Physical training increases isometric muscular strength and proprioceptive performance in haemophilic subjects.

Summary. Sufficient muscular strength and proprioception lessen the risk of joint damage, however, both are impaired in haemophilic subjects. The aim of the study was to investigate proprioceptive performance and isometric muscular strength before and after a specialized training in haemophilic subjects (H) compared with two groups of control subjects (C). Nine subjects with severe haemophilia A, and eight ‘active’ C (AC) without haemophilia took part in a physical training programme over a 6‐month period. Eleven ‘passive’ C (PC) were requested to avoid any additional training during this period. Proprioceptive performance and isometric strength were determined before and after the training programme. The maximal isometric muscular strength in the legs, bilaterally measured by knee extensor (and leg press) was increased (P < 0.05) by 34% (29%) after training in the H and by 20% (28%) in the AC groups while remaining unchanged in the PC group. The performance in one‐leg‐stand tests after training was increased (P < 0.05) in the H and AC groups. An improvement of angle reproduction of 20° and 40° (P < 0.05) in the H compared with the PC groups was seen in the tests. Quantitative sensory testing by the tuning fork showed an increase (P < 0.05) in performance of both H and AC groups. The results of the present study confirm that specific sports therapy focused on proprioceptive function and accompanied by gentle strength training with low resistance and 20–25 repetitions is able to increase proprioceptive performance and muscular strength with a minimal stress to the joints. It is strongly recommended that specialized sports therapy be included as an integral component of the complete treatment regimen of haemophilic subjects.

Physical fitness and heart rate recovery are decreased in major depressive disorder.

Objective: To investigate whether physical fitness is decreased in patients with major depressive disorder (MDD) in comparison to matched healthy controls because low physical fitness has been shown to be associated with metabolic syndrome or autonomic dysfunction. Cardiovascular morbidity and mortality are known to be increased in patients with MDD. Furthermore, the effect of a single exhaustive exercise task on heart rate recovery (HRR) and mood was examined. Methods: Peak oxygen consumption (VO2peak), maximum workload (Ppeak), and individual anaerobic threshold (IAT) were assessed in 22 patients suffering from MDD and 22 controls in a stepwise exhaustion protocol, using spirometry and lactate diagnostics. HRR was detected within the first minute after recovery. The Self-Assessment Manikin (SAM) was used to assess mood before and after exercise. Results: VO2peak, Ppeak, and IAT were decreased significantly in patients, indicating reduced physical fitness in MDD as compared with control subjects. A single exercise exhaustion significantly improved mood in patients, but not in controls. Mood improvement in patients correlated with maximum lactate levels. Significantly reduced HRR values in patients further point to an elevated cardiovascular risk profile and autonomic dysfunction. Conclusions: Our results indicate reduced physical fitness in patients with MDD. Thus, special training programs should be developed to improve their cardiovascular risk profile. In addition, the intriguing finding of a correlation between lactate levels and mood changes should be followed up in future studies to unravel putative mechanisms. BDI = Beck Depression Inventory; BMI = body mass index; CO2 = carbon dioxide; DSM-IV = Diagnostic and Statistical Manual of Mental Disorders, 4th Edition; ECG = electrocardiogram; HAMD-21 = Hamilton Depression Rating Scale; HRR = heart rate recovery; IAT = individual anaerobic threshold; IPAQ = international physical activity questionnaire; MDD = major depressive disorder; MET = metabolic equivalent; Ppeak = maximal work load; RQ = respiratory quotient; rpm = revolutions per minute; SAM = Self-Assessment Manikin; SCID = Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders; VO2 = oxygen consumption; VO2peak = peak oxygen consumption; W = Watt.

Exercise Reveals the Interrelation of Physical Fitness, Inflammatory Response, Psychopathology, and Autonomic Function in Patients With Schizophrenia

Maintaining and improving fitness are associated with a lower risk of premature death from cardiovascular disease. Patients with schizophrenia are known to exercise less and have poorer health behaviors than average. Physical fitness and physiological regulation during exercise tasks have not been investigated to date among patients with schizophrenia. We studied autonomic modulation in a stepwise exhaustion protocol in 23 patients with schizophrenia and in matched controls, using spirometry and lactate diagnostics. Parameters of physical capacity were determined at the aerobic, anaerobic, and vagal thresholds (VT), as well as for peak output. VT was correlated with psychopathology, as assessed by the Positive and Negative Syndrome Scale, with the inflammatory markers IL-1β, IL-6, and TNF-α and with peak output. The MANOVA for heart and breathing rates, as well as for vagal modulation and complexity behavior of heart rate, indicated a profound lack of vagal modulation at all intensity levels, even after the covariate carbon monoxide concentration was introduced as a measure of smoking behavior. Significantly decreased physical capacity was demonstrated at the aerobic, anaerobic, and VT in patients. After the exercise task, reduced vagal modulation in patients correlated negatively with positive symptoms and with levels of IL-6 and TNF-α. This study shows decreased physical capacity in patients with schizophrenia. Upcoming intervention studies need to take into account the autonomic imbalance, which might predispose patients to arrhythmias during exercise. Results of inflammatory parameters are suggestive of a reduced activity of the anti-inflammatory cholinergic pathway in patients, leading to a pro-inflammatory state.

Heart Rate Variability, QT Variability, and Electrodermal Activity during Exercise

PURPOSE Various measures of autonomic function have been developed, and their applicability and significance during exercise are controversial. METHODS Physiological data were therefore obtained from 23 sport students before, during, and after exercise. Measures of R-R interval variability, QT variability index (QTvi), and electrodermal activity (EDA) were calculated. We applied an incremental protocol applying 70%, 85%, 100%, and 110% of the individual anaerobic threshold for standardized comparison. RESULTS Although HR increased stepwise, parasympathetic parameters such as the root mean square of successive differences were not different during exercise and do not mirror autonomic function satisfactorily. Similar results were observed with the approximate entropy of R-R intervals (ApEnRR). In contrast, the increase in sympathetic activity was well reflected in the EDA, QTvi, and ApEn of the QT interval (ApEnQT)/ApEnRR ratio. CONCLUSION We suggest that linear and nonlinear parameters of R-R variability do not adequately reflect vagal modulation. Sympathetic function can be assessed by EDA, QTvi, or ApEnQT/ApEnRR ratio.

Somatosensory Abnormalities for Painful and Innocuous Stimuli at the Back and at a Site Distinct from the Region of Pain in Chronic Back Pain Patients

Chronic low back pain (CLBP) was shown to be associated with pathophysiological changes at several levels of the sensorimotor system. Changes in sensory thresholds have been reported but complete profiles of Quantitative Sensory Testing (QST) were only rarely obtained in CLBP patients. The aim of the present study was to investigate comprehensive QST profiles in CLBP at the painful site (back) and at a site distinct from their painful region (hand) and to compare these data with similar data in healthy controls. We found increased detection thresholds in CLBP patients compared to healthy controls for all innocuous stimuli at the back and extraterritorial to the painful region at the hand. Additionally, CLBP patients showed decreased pain thresholds at both sites. Importantly, there was no interaction between the investigated site and group, i.e. thresholds were changed both at the affected body site and for the site distinct from the painful region (hand). Our results demonstrate severe, widespread changes in somatosensory sensitivity in CLBP patients. These widespread changes point to alterations at higher levels of the neuraxis or/and to a vulnerability to nociceptive plasticity in CLBP patients.

Enhanced sensitivity to punctate painful stimuli in female patients with chronic low back pain

BackgroundChronic low back pain (CLBP) has been shown to be associated with various pathophysiological changes at several level of the sensorimotor system, pointing to a general hypersensitivity in CLBP patients. The aim of the present study was to investigate signs of generalized mechanical pain hypersensitivity in CLBP patients on the hand and on the painful site of the back.MethodsPinprick stimulation according to a validated standardized quantitative sensory testing protocol was used in 14 female CLBP patients and 14 healthy controls (HC) matched for sex and age. Stimulus response functions to pinprick stimulation on the skin were examined at the affected back and reference sites (hand palmar and hand dorsum). Data from CLBP patients were compared with HC and with reference data from the German Research Network on Neuropathic Pain.ResultsWe found significant differences in the stimulus response functions between CLBP patients and HC. Pain ratings to the pinpricks were increased for low and moderate pinprick stimuli in CLBP patients. Importantly, this kind of specific pinprick hyperalgesia was found not only for the affected body site (back), but also for the remote reference sites (hand dorsum and hand palmar).ConclusionsWe interpret our results as pointing to changes in the nociceptive processing in CLBP at higher levels of the neuraxis, possibly thalamus and/or attentional control, rather than changes of spinal processing. Alternatively, there might be a higher vulnerability to noxious stimulation in CLBP patients.

Effects of Resistance Training in Youth Athletes on Muscular Fitness and Athletic Performance: A Conceptual Model for Long-Term Athlete Development

During the stages of long-term athlete development (LTAD), resistance training (RT) is an important means for (i) stimulating athletic development, (ii) tolerating the demands of long-term training and competition, and (iii) inducing long-term health promoting effects that are robust over time and track into adulthood. However, there is a gap in the literature with regards to optimal RT methods during LTAD and how RT is linked to biological age. Thus, the aims of this scoping review were (i) to describe and discuss the effects of RT on muscular fitness and athletic performance in youth athletes, (ii) to introduce a conceptual model on how to appropriately implement different types of RT within LTAD stages, and (iii) to identify research gaps from the existing literature by deducing implications for future research. In general, RT produced small-to-moderate effects on muscular fitness and athletic performance in youth athletes with muscular strength showing the largest improvement. Free weight, complex, and plyometric training appear to be well-suited to improve muscular fitness and athletic performance. In addition, balance training appears to be an important preparatory (facilitating) training program during all stages of LTAD but particularly during the early stages. As youth athletes become more mature, specificity, and intensity of RT methods increase. This scoping review identified research gaps that are summarized in the following and that should be addressed in future studies: (i) to elucidate the influence of gender and biological age on the adaptive potential following RT in youth athletes (especially in females), (ii) to describe RT protocols in more detail (i.e., always report stress and strain-based parameters), and (iii) to examine neuromuscular and tendomuscular adaptations following RT in youth athletes.

Hippocampal structure, metabolism, and inflammatory response after a 6-week intense aerobic exercise in healthy young adults: a controlled trial

Interventional studies suggest that changes in physical fitness affect brain function and structure. We studied the influence of high intensity physical exercise on hippocampal volume and metabolism in 17 young healthy male adults during a 6-week exercise program compared with matched controls. We further aimed to relate these changes to hypothesized changes in exercised-induced brain-derived neurotrophic factor (BDNF), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α). We show profound improvement of physical fitness in most subjects and a positive correlation between the degree of fitness improvement and increased BDNF levels. We unexpectedly observed an average volume decrease of about 2%, which was restricted to right hippocampal subfields CA2/3, subiculum, and dentate gyrus and which correlated with fitness improvement and increased BDNF levels negatively. This result indicates that mainly those subjects who did not benefit from the exercise program show decreased hippocampal volume, reduced BDNF levels, and increased TNF-α concentrations. While spectroscopy results do not indicate any neuronal loss (unchanged N-acetylaspartate levels) decreased glutamate-glutamine levels were observed in the right anterior hippocampus in the exercise group only. Responder characteristics need to be studied in more detail. Our results point to an important role of the inflammatory response after exercise on changes in hippocampal structure.

Influence of delayed muscle reflexes on spinal stability: model-based predictions allow alternative interpretations of experimental data.

Model-based calculations indicate that reflex delay and reflex gain are both important for spinal stability. Experimental results demonstrate that chronic low back pain is associated with delayed muscle reflex responses of trunk muscles. The aim of the present study was to analyze the influence of such time-delayed reflexes on the stability using a simple biomechanical model. Additionally, we compared the model-based predictions with experimental data from chronic low back pain patients and healthy controls using surface-electromyography. Linear stability methods were applied to the musculoskeletal model, which was extended with a time-delayed reflex model. Lateral external perturbations were simulated around equilibrium to investigate the effects of reflex delay and gain on the stability of the human lumbar spine. The model simulations predicted that increased reflex delays require a reduction of the reflex gain to avoid spinal instability. The experimental data support this dependence for the investigated abdominal muscles in chronic low back pain patients and healthy control subjects. Reflex time-delay and gain dependence showed that a delayed reflex latency could have relevant influence on spinal stability, if subjects do not adapt their reflex amplitudes. Based on the model and the experimental results, the relationship between muscle reflex response latency and the maximum of the reflex amplitude should be considered for evaluation of (patho) physiological data. We recommend that training procedures should focus on speeding up the delayed reflex response as well as on increasing the amplitude of these reflexes.

Chronischer unspezifischer Rückenschmerz

ZusammenfassungDer chronische unspezifische Rückenschmerz ist ein zentrales Thema für Patienten, Versicherer und Berufsgenossenschaften. Mit einer Präventivdiagnostik bestünde die Möglichkeit, für einen momentan beschwerdefreien Menschen eine Prognose zu erstellen, mit welcher Wahrscheinlichkeit er einen chronischen unspezifischen Rückenschmerz erleiden wird, wenn er sich nicht einer präventiven Maßnahme unterzieht.Jedes Jahr erleiden 20% der Erwachsenen Rückenschmerzen und 70–80% der Bevölkerung bekommen in ihrem Leben einmal oder mehrmals Rückenschmerzen. Meist reduzieren sich die Beschwerden innerhalb der ersten sechs Wochen ohne medizinische Intervention oder verschwinden ganz. Nur in wenigen Fällen sind sie progredient, chronifizieren und verursachen erhebliche Kosten.Es gilt herauszufinden, ob eine Person zu einer Risikogruppe gezählt werden kann, für die zukünftig eine Chronifizierung des Rückenschmerzes wahrscheinlich wird. Mit dem präventivdiagnostischen Ansatz sollte die Frage beantwortet werden können: Welche Subgruppe von Patienten mit chronischem Rückenschmerz wird besonders von einer Übungstherapie oder von kognitiven verhaltenstherapeutischen Ansätzen profitieren?AbstractChronic low back pain represents an important issue not only for the patients but also for society. Apreventive diagnosis could open the possibility to predict the individual probability of developing chronic low back pain in pain-free persons or persons with sub-acute low back pain if no further preventive interventions would be started.Every year about 20% of adults will suffer from back pain and 70-80% of society will suffer from back pain during their lives. In most cases back pain is alleviated within the first 6 weeks without any medical intervention. Only a few cases are progredient and chronic with immense costs for society and health care systems.It is necessary to find out which individuals will probably suffer from chronic back pain in the future. The diagnostic outcome of the classification should help to answer the question which subgroups of patients with chronic low back pain will especially benefit from exercise therapy or cognitive behavior therapy?