Low-frequency Trains Research Articles

The effects of high versus low frequency of combined physical and cognitive training on cognitive function in older adults with cognitive decline: a quasi-experimental study

BackgroundThe effects of combined training can be affected by training characteristics such as frequency, session length, and duration. No empirical studies to date have directly compared how combined physical and cognitive training offered at different training frequencies affects cognitive function for older adults with cognitive decline. This study investigated the impact of training frequency on cognitive outcomes after combined physical and cognitive training for older adults with cognitive decline.MethodsA quasi-experimental study was conducted in community facilities and day care centers. The study assigned 89 older adults with cognitive decline into high-frequency (HF) or low-frequency (LF) training groups. The participants received 90- to 105-min training sessions, one (LF) or three (HF) times a week, for 12 weeks. Outcome measures were the Montreal Cognitive Assessment, Word List subtest of the Wechsler Memory Scale, Digit Symbol Substitution Test (DSST), and Stroop Color Word Test.ResultsThe HF group demonstrated greater improvement in immediate memory measured by the WL-IM (F = 8.7, P = 0.004) and in executive function measured by the SCWT (F = 5.89, P = 0.017) than the LF group. Compared with the HF group, the LF group showed a great improvement in delayed memory measured by the WL-DM (F = 9.62, P = 0.003). The HF and LF groups both increased in processing speed and global cognitive function.ConclusionsOur study indicated that the different training frequency of combined physical and cognitive training may result in benefits on different cognitive functions in older adults with cognitive decline. These findings may assist clinical practitioners in choosing appropriate training frequencies based on various intervention purposes for the elderly with cognitive decline.Trial registrationClinicalTrials.gov Identifier NCT03619577 (08/08/2018).

Effect of aerobic exercise training frequency on arterial stiffness in middle-aged and elderly females.

[Purpose] This study aimed to determine the effects of aerobic exercise training frequency on arterial stiffness in postmenopausal females. [Participants and Methods] This study included 45 postmenopausal females randomly assigned to one of the following three groups: 1) low-frequency training group (aerobic exercise training twice per week); 2) high-frequency training group (aerobic exercise training four times per week); and 3) control group (no training). Each group was subjected to an 8-week intervention period. Both traditional and newer indexes were measured immediately before and after the 8-week intervention period. [Results] In the low-frequency training group, carotid-femoral pulse wave velocity and arterial velocity pulse index decreased post 8 weeks compared with those at baseline. In the high-frequency training group, carotid-femoral, brachial-ankle, and heart-brachial pulse wave velocities and arterial velocity pulse and arterial pressure-volume indexes decreased post 8 weeks compared to those at baseline. In the control group, no change in any indices post 8 weeks compared to those at baseline was observed. [Conclusion] Carotid-femoral pulse wave velocity was lower after aerobic training than before training in both the exercise groups. Thus, aerobic exercise training might have a beneficial effect on aortic stiffness, regardless of the training frequency in this population.

Achieving physical examination competence through optimizing hands-on practice cycles: a prospective cohort comparative study of medical students.

BackgroundDeliberate practice (DP) was proposed for effective clinical skill training, which highlights focused, repetitive practice and feedback as the key points for practice. Although previous studies have investigated the effect of feedback in DP, little is known about the proper repetitive cycles of clinical skills training especially in physical examination (PE) training.MethodsWe drew learning curves and designed a comparative study to find out the optimal number of hands-on practice cycles, an important aspect of DP, in abdominal PE training for medical students. A comparative study was conducted to validate the optimal number of hands-on practice by dividing students into two cohorts including Cohort A (high-frequency hand-on training) and B (low-frequency hand-on training).ResultsThe learning curve study of 16 students exhibited a threshold of four repetitive practices when 81.25% students reached the competence score. A total of 74 students’ final exam scores were collected for analysis. Students in Cohort A (4–5 PEs) scored significantly higher than those in Cohort B (≤3 PEs) (84.41 ± 11.78 vs 76.83 ± 17.51] in the final exam (P = 0.030)).ConclusionHigh-frequency practice can improve students’ competence of abdominal PE skill. We recommend four cycles of hands-on practice for each student in a training course like PE training.

Low-frequency exercise training improves cardiovascular fitness and strength during treatment for breast cancer: a single-arm intervention study

Aerobic and resistance exercise during and after cancer treatment are important for health-related outcomes, however treatment-specific barriers may inhibit adherence. We explored the effect of lower-frequency exercise training on fitness, body composition, and metabolic markers (i.e. glucose and lipids) in a group of recently diagnosed breast cancer patients. Fifty-two females ≥ 18 years with stage I–IIIB breast cancer were instructed to attend 2 cardiovascular and strength training sessions/week over 12 weeks, but program length was expanded as needed to accommodate missed sessions. Pre- and post-intervention, we measured: (1) cardiovascular fitness, (2) isometric strength, (3) body composition (dual-energy X-ray absorptiometry), and (4) fasting glucose, insulin, c-peptide, and lipids. Pre-intervention, participants were 53 ± 10 years old (mean ± SD) and overweight (BMI: 27.5 ± 5.4 kg m−2, 40.1 ± 6.5% body fat). Forty participants completed the program over a median 20 weeks (range: 13–32 weeks, median frequency: 1.2 sessions/week), over which predicted VO2peak improved by 7% (2.2[0.1–4.4] mL/kg/min) (delta[95% CI]), and strength increased by 7–9% (right arm: 2.3[0.1–4.5] N m; right leg: 7.9[2.1–13.7] N m; left leg: 7.8[1.9–13.7] N m). Body composition and metabolic markers were unchanged. An exercise frequency of 1.2 sessions/week stimulated significant improvements in fitness, and may represent a practical target for patients during active treatment.

Identification of Good Practices in Long-Term Exercise-Based Rehabilitation Programs in Stroke Patients.

Physical activity is an important factor for primary and secondary stroke prevention. The process of stroke rehabilitation includes early and late physical activity and exercise, which prevents further stoke and improve patients' quality of life. MY WAY project, an ERASMUS+ SPORT program, is aimed at analyzing and developing or transferring best innovative practices related to physical activity and exercise enhancing health in poststroke patients. The aim of the study was to identify, analyze, and present the good practices and strategies to encourage participation in sport and physical activity and engage and motivate chronic stroke patients to perform physical activity changing their lifestyle and to maintain a high adherence to long-term exercise-based rehabilitation programs. Our results demonstrated that unified European stroke long-term exercise-based rehabilitation guidelines do not exist. It seems that low training frequency with high aerobic exercise intensity may be optimal for improved physical performance and quality of life in combination with a high adherence. It is important to optimize the training protocols suitable for each patient. The continuous education and training of the specialized professionals in this field and the presence of adequate structures and cooperation between different healthcare centers are important contributors. The clear objective for each country should be to systematically make the necessary steps to enhance overall exercise-based stroke rehabilitation attendance in the long term. Long-term interventions to support the importance of physical exercise and lifelong exercise-based rehabilitation in chronic stroke patients should be created, what coincides with the goal of the MY WAY project.

α3β4∗ Nicotinic Acetylcholine Receptors Strongly Modulate the Excitability of VIP Neurons in the Mouse Inferior Colliculus.

The inferior colliculus (IC), the midbrain hub of the central auditory system, receives extensive cholinergic input from the pontomesencephalic tegmentum. Activation of nicotinic acetylcholine receptors (nAChRs) in the IC can alter acoustic processing and enhance auditory task performance. However, how nAChRs affect the excitability of specific classes of IC neurons remains unknown. Recently, we identified vasoactive intestinal peptide (VIP) neurons as a distinct class of glutamatergic principal neurons in the IC. Here, in experiments using male and female mice, we show that cholinergic terminals are routinely located adjacent to the somas and dendrites of VIP neurons. Using whole-cell electrophysiology in brain slices, we found that acetylcholine drives surprisingly strong and long-lasting excitation and inward currents in VIP neurons. This excitation was unaffected by the muscarinic receptor antagonist atropine. Application of nAChR antagonists revealed that acetylcholine excites VIP neurons mainly via activation of α3β4∗ nAChRs, a nAChR subtype that is rare in the brain. Furthermore, we show that acetylcholine excites VIP neurons directly and does not require intermediate activation of presynaptic inputs that might express nAChRs. Lastly, we found that low frequency trains of acetylcholine puffs elicited temporal summation in VIP neurons, suggesting that in vivo-like patterns of cholinergic input can reshape activity for prolonged periods. These results reveal the first cellular mechanisms of nAChR regulation in the IC, identify a functional role for α3β4∗ nAChRs in the auditory system, and suggest that cholinergic input can potently influence auditory processing by increasing excitability in VIP neurons and their postsynaptic targets.

Improved metabolic fitness, but no cardiovascular health effects, of a low-frequency short-term combined exercise programme in 50–70-year-olds with low fitness: A randomized controlled trial

ABSTRACT We evaluated the cardiometabolic effects of a 15-week combined exercise programme, implemented in sports clubs, for 50–70-year-olds with low aerobic fitness. In a randomized controlled trial, 45 participants (26 women) with low fitness were randomly assigned (2:1-ratio) to a training group (TG, n = 30) or inactive control group (CG, n = 15). TG had 15 weeks with one weekly 90-min supervised group-based session in a recreational sports club with combined aerobic exercise and strength training and were encouraged to perform home-based training 30 min/wk. Evaluations of relative VO2max (mLO2/min/kg), blood pressure, resting heart rate (HR), echocardiography, peripheral arterial tonometry, body composition, lipid profile and HbA1c were performed at 0 and 15 wks. Average HR during supervised training was 113 ± 13 bpm (68.6 ± 7.0%HRmax), with 4.3 ± 6.6% spent >90%HRmax. At 15-wk follow-up, intention-to-treat analyses revealed no between-group difference for VO2max/kg (0.4 mLO2/min/kg, 95%CI −0.8–1.5, P = 0.519; −3 mL/min, 95%CI −123–118, P = 0.966) or other cardiovascular outcomes (all P > 0.05). Compared to CG, total fat mass (−1.9 kg; 95%CI −3.2 to −0.5, P = 0.005), total fat percentage (−1.3%, 95%CI −2.2 to −0.3, P = 0.01) and total/HDL cholesterol ratio (P = 0.032) decreased in TG. Regular adherence to supervised training was high (81%), but 0% for home-based exercise. In conclusion, the group-based supervised training was associated with high adherence and moderate exercise intensity, whereas insufficiently supported home-based training was not feasible. Together, 15 wks of combined exercise training did not improve aerobic fitness or affected cardiovascular function in 50–70-yr-olds with low aerobic fitness, whereas some positive effects were observed in metabolic parameters. Highlights Combined exercise training implemented in a sports club elicited moderate aerobic intensity in 50-70-year-old untrained individuals. Supervised group-based training had high adherence whereas unsupported home-based training had very low adherence. 15 weeks of low-frequency combined moderate intensity exercise training improved lipid profile and fat mass, but had no effect on cardiovascular fitness.

Networking of glucagon-like peptide-1 axons with GnRH neurons in the basal forebrain of male mice revealed by 3DISCO-based immunocytochemistry and optogenetics

Glucagon-like peptide-1 (GLP-1) regulates reproduction centrally, although, the neuroanatomical basis of the process is unknown. Therefore, the putative networking of the central GLP-1 and gonadotropin-releasing hormone (GnRH) systems was addressed in male mice using whole mount immunocytochemistry and optogenetics. Enhanced antibody penetration and optical clearing procedures applied to 500–1000 µm thick basal forebrain slices allowed the simultaneous visualization of the two distinct systems in the basal forebrain. Beaded GLP-1-IR axons innervated about a quarter of GnRH neurons (23.2 ± 1.4%) forming either single or multiple contacts. GnRH dendrites received a more intense GLP-1 innervation (64.6 ± 0.03%) than perikarya (35.4 ± 0.03%). The physiological significance of the innervation was examined by optogenetic activation of channelrhodopsin-2 (ChR2)-expressing axons of preproglucagon (GCG) neurons upon the firing of GnRH neurons by patch clamp electrophysiology in acute brain slices of triple transgenic mice (Gcg-cre/ChR2/GFP-GnRH). High-frequency laser beam stimulation (20 Hz, 10 ms pulse width, 3 mW laser power) of ChR2-expressing GCG axons in the mPOA increased the firing rate of GnRH neurons (by 75 ± 17.3%, p = 0.0007). Application of the GLP-1 receptor antagonist, Exendin-3-(9-39) (1 μM), prior to the photo-stimulation, abolished the facilitatory effect. In contrast, low-frequency trains of laser pulses (0.2 Hz, 60 pulses) had no effect on the spontaneous postsynaptic currents of GnRH neurons. The findings indicate a direct wiring of GLP-1 neurons with GnRH cells which route is excitatory for the GnRH system. The pathway may relay metabolic signals to GnRH neurons and synchronize metabolism with reproduction.

Bicycle parking at train stations in the Netherlands: Travellers' behaviour and policy options

The combined use of bicycles and trains is a popular means of transport in the Netherlands, experiencing strong growth in recent years. This development is in line with the Dutch Ministry of Infrastructure and Water Management's policy goal of promoting cycling as a stand-alone mode, and in combination with trains. Such active travel policies generate social benefits, such as improved public health, reduced emissions and less congestion.The success of combined bike and train use in the Netherlands however has unresolved issues. Due to overcrowded bicycle storage facilities at large train stations, many bicycles are parked outside these facilities, resulting in public nuisance and inefficient use of space in the areas around train stations. Concurrently, the continued growth of combined bicycle-train use is desired. The policy question therefore is how to facilitate growth while accounting for the current bicycle parking problem. In tackling this challenge, this paper aims to shed more light on the bicycle parking behaviour of bicycle-train travellers.In cooperation with Dutch National Railways, train travellers were given a questionnaire designed to elicit information about their travel behaviour during the two-week period preceding the questionnaire's completion date. More than 3000 questionnaires were completed. Descriptive statistics and binary logit models were used to analyse the resulting data.We found that the privately owned bicycles used on a train trips' activity-end (the so-called ‘second bicycles’) were parked at train station parking facilities approximately four times longer than bicycles used at the train trips' home-end station. Initial estimates revealed that these second bicycles accounted for at least 45% of the bicycle parking pressure witnessed at all train stations in the Netherlands. We also found that among second bicycle owners, low-frequency train use, and using activity-end train stations located in suburbs, are positively associated with long term bicycle parking on the activity-end. Moreover, of all the times bicycles are parked, approximately 10% of activity-end bicycles, and 20% of home-end bicycles, are parked unguarded outside of train station parking facilities. There is a lower probability of home-end bicycles being parked outside of bicycle parking facilities at small train stations than at large stations.Possible solutions to the bicycle parking problem include offering more shared bicycles as alternatives to second bicycles, striving to ban second bicycles from racks situated close to train platforms (by means of pricing and enforcement), and locating parking spaces specifically designated for second bicycles further away from train platforms. This would free up parking spaces close to platforms for home-end bicycles, which are more frequently rotated in and out. Additionally, to further alleviate the parking problem, an awareness-and-warning campaign could be directed at those who wrongly park their home-end bicycles.

Age-dependent effects of protein restriction on dopamine release

Despite the essential role of protein intake for health and development, very little is known about the impact of protein restriction on neurobiological functions, especially at different stages of the lifespan. The dopamine system is a central actor in the integration of food-related processes and is influenced by physiological state and food-related signals. Moreover, it is highly sensitive to dietary effects during early life periods such as adolescence due to its late maturation. In the present study, we investigated the impact of protein restriction either during adolescence or adulthood on the function of the mesolimbic (nucleus accumbens) and nigrostriatal (dorsal striatum) dopamine pathways using fast-scan cyclic voltammetry in rat brain slices. In the nucleus accumbens, protein restriction in adults increased dopamine release in response to low and high frequency trains of stimulation (1–20 Hz). By contrast, protein restriction during adolescence decreased nucleus accumbens dopamine release. In the dorsal striatum, protein restriction at adulthood has no impact on dopamine release but the same diet during adolescence induced a frequency-dependent increase in stimulated dopamine release. Taken together, our results highlight the sensitivity of the different dopamine pathways to the effect of protein restriction, as well as their vulnerability to deleterious diet effects at different life stages.

Resistance Training Status and Effectiveness of Low-Frequency Resistance Training on Upper-Body Strength and Power in Highly Trained Soccer Players.

Hertzog, M, Rumpf, MC, and Hader, K. Resistance training status and effectiveness of low-frequency resistance training on upper-body strength and power in highly trained soccer players. J Strength Cond Res 34(4): 1032-1039, 2020-Soccer is classified as a contact/collision sport with many player-to-player duels. Winning these duels, shielding the ball or fending off an opponent requires upper-body strength and power. Therefore, this study aimed (a) to examine the time-related effect of an upper-body resistance training (RT) on maximal strength and power changes in highly trained soccer players and (b) to investigate if the RT status influences these changes throughout a competitive season. Twenty-eight soccer players participated in this study and were divided into an untrained group (UG) and a trained group (TG), according to their RT status. Both groups performed the same upper-body RT once a week, over 30 weeks. Maximal strength (1 repetition maximum [1RM]) and maximal power (MP) were assessed before, during, and after the competitive season. Both groups significantly improved 1RM and MP over the entire competitive season, with a moderate (TG, 13%) to very large (UG, 21%) magnitude in 1RM and with a small (TG, 8%) to moderate (UG, 13%) magnitude in MP. After the initial 10 weeks of RT, UG presented significant and slightly (1RM) to moderately (MP) greater improvements than TG. For all other time intervals, the between-groups' changes in 1RM were rated as similar. For the last 20 weeks of the RT, the change in MP was significantly lower for UG compared with TG. One upper-body RT session per week will provide sufficient stimulus to enable an almost certain improvement in strength and power throughout a competitive season for all players disregarding their initial RT status.

Spatial Frequency Tuning and Transfer of Perceptual Learning for Motion Coherence Reflects the Tuning Properties of Global Motion Processing.

Perceptual learning is typically highly specific to the stimuli and task used during training. However, recently, it has been shown that training on global motion can transfer to untrained tasks, reflecting the generalising properties of mechanisms at this level of processing. We investigated (i) if feedback was required for learning in a motion coherence task, (ii) the transfer across the spatial frequency of training on a global motion coherence task and (iii) the transfer of this training to a measure of contrast sensitivity. For our first experiment, two groups, with and without feedback, trained for ten days on a broadband motion coherence task. Results indicated that feedback was a requirement for robust learning. For the second experiment, training consisted of five days of direction discrimination using one of three motion coherence stimuli (where individual elements were comprised of either broadband Gaussian blobs or low- or high-frequency random-dot Gabor patches), with trial-by-trial auditory feedback. A pre- and post-training assessment was conducted for each of the three types of global motion coherence conditions and high and low spatial frequency contrast sensitivity (both without feedback). Our training paradigm was successful at eliciting improvement in the trained tasks over the five days. Post-training assessments found evidence of transfer for the motion coherence task exclusively for the group trained on low spatial frequency elements. For the contrast sensitivity tasks, improved performance was observed for low- and high-frequency stimuli, following motion coherence training with broadband stimuli, and for low-frequency stimuli, following low-frequency training. Our findings are consistent with perceptual learning, which depends on the global stage of motion processing in higher cortical areas, which is broadly tuned for spatial frequency, with a preference for low frequencies.

Low-frequency High-Intensity Interval Training in Overweight or Obese Young Adults

Low-frequency High-Intensity Interval Training in Overweight or Obese Young Adults

Effect of Electrical Stimulation Frequency and Pattern on Muscle Fatigue in Spinal Cord Injured Individuals

Spinal cord injury (SCI) leads to an extensive skeletal muscle atrophy in the regions below the level of injury. Moreover, the paralyzed skeletal muscles shift towards predominantly Type II (fast‐twitch and highly fatigable) fibers. Functional electrical stimulation (FES) has been used to produce purposeful and controlled muscle contractions to restore functional movements, but rapid muscle fatigue remains a problem. Both pattern and frequency of stimulation can influence muscle fatigue rate, but optimization of stimulation parameters has rarely been investigated for those with SCI. FES has traditionally used constant‐frequency trains (CFT; brief stimulation pulses separated by regular interpulse intervals). However, it has been suggested that doublet‐frequency trains (DFT; close‐spaced pulse trains separated by longer intervals) can result in lesser fatigue. Also, stimulation frequency may determine muscle fatigue, with high‐frequency trains resulting in lesser fatigue compared to low‐frequency trains. However, most studies comparing muscle fatigue across stimulation parameters have been only examined in able‐bodied individuals and it is unknown whether paralyzed muscles respond similarly. There are a few studies suggesting that low‐frequency trains produce less fatigue than high‐frequency trains in those with SCI, in direct contrast to the able‐bodied. Therefore, we examined differences in muscle fatigue across and within able‐bodied individuals (N=8) and those with SCI (N=6) during CFT and DFT stimulation patterns at high‐ (40 Hz) and low‐ (20 Hz) frequencies. Fatigue was defined as a sustained reduction in force of >20% at a constant stimulation intensity. Differences were considered significant at p<0.05 and values are mean ± SEM. For both groups, low‐frequency trains delayed fatigue onset compared to high‐frequency trains, on average by 30 ± 3 %. In the able‐bodied, CFT resulted in slower fatigue onset (#contractions to fatigue CFT vs DFT: 20 Hz 39 ± 4 vs. 34 ± 4, 40 Hz 26 ± 4 vs. 23 ± 3). In those with SCI, DFT resulted in slower fatigue onset (#contractions to fatigue CFT vs DFT: 20 Hz 26 ± 2 vs. 35 ± 4, 40 Hz 20 ± 2 vs. 25 ± 2). In fact, DFT resulted in similar #contractions to fatigue in both populations, whereas CFT induced muscle fatigue significantly faster in those with SCI. These results may indicate that DFT preferentially recruit fast‐twitch fibers, leading to similar fatigue in both able‐bodied and those with SCI. DFT has been previously shown to limit fatigue potentially by increasing calcium release from the sarcoplasmic reticulum and/or by increasing muscle stiffness. These data indicate that DFT trains appear to be preferable for fatigue reduction in the SCI population.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Effects of different strength training frequencies on maximum strength, body composition and functional capacity in healthy older individuals

There is controversy in the literature regarding the dose-response relationship of strength training in healthy older participants. The present study determined training frequency effects on maximum strength, muscle mass and functional capacity over 6months following an initial 3-month preparatory strength training period. One-hundred and six 64–75year old volunteers were randomly assigned to one of four groups; performing strength training one (EX1), two (EX2), or three (EX3) times per week and a non-training control (CON) group. Whole-body strength training was performed using 2–5 sets and 4–12 repetitions per exercise and 7–9 exercises per session. Before and after the intervention, maximum dynamic leg press (1-RM) and isometric knee extensor and plantarflexor strength, body composition and quadriceps cross-sectional area, as well as functional capacity (maximum 7.5m forward and backward walking speed, timed-up-and-go test, loaded 10-stair climb test) were measured. All experimental groups increased leg press 1-RM more than CON (EX1: 3±8%, EX2: 6±6%, EX3: 10±8%, CON: −3±6%, P<0.05) and EX3 improved more than EX1 (P=0.007) at month 9. Compared to CON, EX3 improved in backward walk (P=0.047) and EX1 in timed-up-and-go (P=0.029) tests. No significant changes occurred in body composition. The present study found no evidence that higher training frequency would induce greater benefit to maximum walking speed (i.e. functional capacity) despite a clear dose-response in dynamic 1-RM strength, at least when predominantly using machine weight-training. It appears that beneficial functional capacity improvements can be achieved through low frequency training (i.e. 1–2 times per week) in previously untrained healthy older participants.

Positive effects of plantar vibration training for the treatment of diabetic peripheral neuropathy: A pilot study

Purpose: To evaluate the effectiveness of 8-week low-frequency plantar vibration training on patients with sensorimotor diabetic peripheral neuropathy (DPN).Participants: Twelve patients took part in the investigation.Results: An increase of the nerve conductive velocity of soral and peroneal nerves of feet, increased postural stability, and disappearance of the pain and tingling were observed.Conclusion: The obtained results provide evidence for beneficial effects of 8-week plantar vibration training in patients with DPN.

Influence of clinical results of early low frequency training for acute Achilles tendon rupture after anchors repair

Objective To investigate the influence of clinical results of early low frequency training for acute Achilles tendon rupture after anchors repair. Methods A total of 35 patients with acute Achilles tendon rupture were treated with early low frequency training after anchors repair, including 28 males and 7 females.Aged 18 to 37 years, mean 26 years old.Duration 2h to 5d from injury to therapy.All patients palpated the discontinuity of Achilles tendon, limitative activity of ankle plantar flexion, Thompson test was positive, and MRI examination was taken. Results 35 patients were followed up for 12 to 18 months, with an average follow-up of 14.5 months.According to the Amer-Lindholm score, excellent in 30 cases, good in 5 cases, the good rate was 100%.All the wounds were healed, without infection, dehiscence, sural nerve injury and re-rupture occurred. Conclusion Early low frequency training after anchors repair for acute Achilles tendon rupture is safe and reliable, patients can receive a better functional outcome. Key words: Early training; Achilles tendon; Anchor; Surgery

Similar enhancement of BK(Ca) channel function despite different aerobic exercise frequency in aging cerebrovascular myocytes.

Aerobic exercise showed beneficial influence on cardiovascular systems in aging, and mechanisms underlying vascular adaption remain unclear. Large-conductance Ca(2+)-activated K(+) (BK(Ca)) channels play critical roles in regulating cellular excitability and vascular tone. This study determined the effects of aerobic exercise on aging-associated functional changes in BK(Ca) channels in cerebrovascular myocytes, Male Wistar rats aged 20-22 months were randomly assigned to sedentary (O-SED), low training frequency (O-EXL), and high training frequency group (O-EXH). Young rats were used as control. Compared to young rats, whole-cell BK(Ca) current was decreased, and amplitude of spontaneous transient outward currents were reduced. The open probability and Ca(2+)/voltage sensitivity of single BK(Ca) channel were declined in O-SED, accompanied with a reduction of tamoxifen-induced BK(Ca) activation; the mean open time of BK(Ca) channels was shortened whereas close time was prolonged. Aerobic exercise training markedly alleviated the aging-associated decline independent of training frequency. Exercise three times rather than five times weekly may be a time and cost-saving training volume required to offer beneficial effects to offset the functional declines of BK(Ca) during aging.

Ageing, Muscle Power and Physical Function: A Systematic Review and Implications for Pragmatic Training Interventions.

The physiological impairments most strongly associated with functional performance in older people are logically the most efficient therapeutic targets for exercise training interventions aimed at improving function and maintaining independence in later life. The objectives of this review were to (1) systematically review the relationship between muscle power and functional performance in older people; (2) systematically review the effect of power training (PT) interventions on functional performance in older people; and (3) identify components of successful PT interventions relevant to pragmatic trials by scoping the literature. Our approach involved three stages. First, we systematically reviewed evidence on the relationship between muscle power, muscle strength and functional performance and, second, we systematically reviewed PT intervention studies that included both muscle power and at least one index of functional performance as outcome measures. Finally, taking a strong pragmatic perspective, we conducted a scoping review of the PT evidence to identify the successful components of training interventions needed to provide a minimally effective training dose to improve physical function. Evidence from 44 studies revealed a positive association between muscle power and indices of physical function, and that muscle power is a marginally superior predictor of functional performance than muscle strength. Nine studies revealed maximal angular velocity of movement, an important component of muscle power, to be positively associated with functional performance and a better predictor of functional performance than muscle strength. We identified 31 PT studies, characterised by small sample sizes and incomplete reporting of interventions, resulting in less than one-in-five studies judged as having a low risk of bias. Thirteen studies compared traditional resistance training with PT, with ten studies reporting the superiority of PT for either muscle power or functional performance. Further studies demonstrated the efficacy of various methods of resistance and functional task PT on muscle power and functional performance, including low-load PT and low-volume interventions. Maximal intended movement velocity, low training load, simple training methods, low-volume training and low-frequency training were revealed as components offering potential for the development of a pragmatic intervention. Additionally, the research area is dominated by short-term interventions producing short-term gains with little consideration of the long-term maintenance of functional performance. We believe the area would benefit from larger and higher-quality studies and consideration of optimal long-term strategies to develop and maintain muscle power and physical function over years rather than weeks.

A simple effective model for STDP: from spike pairs and triplets to rate-encoding plasticity

In the present work [1] we propose an effective model formulating synaptic potentiation and depression in terms of two interacting traces, representing the fraction of open NMDA receptors and the Ca2+ concentration in the post-synaptic neuron, respectively. These two traces then determine the evolution of the synaptic strength. We first confirm that the standard pairwise STDP curve is obtained for low frequency trains of pairs of pre- and post-synaptic spikes and we then evaluate triplet effects (see Figure ​Figure1),1), comparing the model's results to experimental data from hippocampal culture [2,3]. Finally, we evaluate the model's predictions for spike trains of different frequencies and degrees of correlation, observing that a BCM-like rule for plasticity as a function of the pre-and post-synaptic firing rates is recovered when employing uncorrelated poisson trains of pre- and postsynaptic spikes. Figure 1 Model's prediction and comparison to experimental results from hippocampal culture. A . The standard pairwise STDP curve is recovered by the model. Blue lines indicate the model's results and red circles the experimental data [2]. B . Triplets, consisting ... Having a low number of parameters and being composed of only polynomial differential equations, the model is able nonetheless to reproduce key features of LTP and LTD. Moreover, since the parameters of the model are easily related to the dynamical properties of the synapse, we believe the model constitutes a useful tool to study extended neural networks from a dynamical system's point of view.