Aerobic Training in Patients with Congenital Myopathy

Introduction

Congenital myopathies (CM) often affect contractile proteins of the sarcomere, which could render patients susceptible to exercise-induced muscle damage. We investigated if exercise is safe and beneficial in patients with CM.

Methods

Patients exercised on a stationary bike for 30 minutes, three times weekly, for 10 weeks at 70% of their maximal oxygen uptake (VO_2max). Creatine kinase (CK) was monitored as a marker of muscle damage. VO_2max, functional tests, and questionnaires evaluated efficacy.

Results

Sixteen patients with CM were included in a controlled study. VO_2max increased by 14% (range, 6–25%; 95% CI 7–20; p < 0.001) in the seven patients who completed training, and tended to decrease in a non-intervention group (n = 7; change -3.5%; range, -11–3%, p = 0.083). CK levels were normal and remained stable during training. Baseline Fatigue Severity Scale scores were high, 4.9 (SE 1.9), and tended to decrease (to 4.4 (SE 1.7); p = 0.08) with training. Nine patients dropped out of the training program. Fatigue was the major single reason.

Conclusions

Ten weeks of endurance training is safe and improves fitness in patients with congenital myopathies. The training did not cause sarcomeric injury, even though sarcomeric function is affected by the genetic abnormalities in most patients with CM. Severe fatigue, which characterizes patients with CM, is a limiting factor for initiating training in CM, but tends to improve in those who train.

Trial Registration

The Regional Committee on Health Research Ethics of the Capital Region of Denmark H-2-2013-066 and ClinicalTrials.gov H2-2013-066     

Effects of Small-Sided Games vs. Interval Training in Aerobic Fitness and Physical Enjoyment in Young Elite Soccer Players

The purpose of this study was to compare the effects of Small-Sided Games (SSG) vs. Interval Training (IT) in soccer training on aerobic fitness and physical enjoyment in youth elite soccer players during the last 8 weeks of the season. Seventeen U-16 male soccer players (age = 15.5 ± 0.6 years, and 8.5 years of experience) of a Spanish First Division club academy were randomized to 2 different groups for 6 weeks: SSG group (n = 9) and IT group (n = 8). In addition to the usual technical and tactical sessions and competitive games, the SSG group performed 11 sessions with different SSGs, whereas the IT group performed the same number of sessions of IT. Players were tested before and after the 6-week training intervention with a continuous maximal multistage running field test and the counter movement jump test (CMJ). At the end of the study, players answered the physical activity enjoyment scale (PACES). During the study, heart rate (HR) and session perceived effort (sRPE) were assessed. SSGs were as effective as IT in maintaining the aerobic fitness in elite young soccer players during the last weeks of the season. Players in the SSG group declared a greater physical enjoyment than IT (P = 0.006; ES = 1.86 ± 1.07). Coaches could use SSG training during the last weeks of the season as an option without fear of losing aerobic fitness while promoting high physical enjoyment.     

Effects of Inspiratory Strength Training on the Detection of Inspiratory Loads

Pressure-threshold loads (ΔPT) are inspiratory force-related loads, which contrast with resistive loads (ΔR), are airflow-dependent loads. If detection of respiratory loads is a function of the background load, then pressure-threshold type inspiratory muscle strength training (IMST) would affect the detection of ΔPT but have less effect on detection of ΔR. ΔR and ΔPT detection and ventilatory responses were measured in healthy volunteers. IMST consisted of 4 sets of 6 breaths per day for 4 weeks, at 75% of maximal inspiratory pressure (MIP). MIP increased and a measure of inspiratory dirve, the mouth pressure generated in the initial 100 msec of an occluded inspiration (P_0.1), decreased after IMST. IMST significantly increased MIP after 4 weeks of training. IMST did not change ΔR detection threshold and ΔR-breathing pattern. IMST decreased ΔPT detection percent and ΔPT-breathing pattern. Comparing ΔR and ΔPT at the same mouth pressure-generating level, the detection percent was different. We conclude that IMST affects the detection of ΔPT, but not ΔR. These results also suggest that mouth pressure is not the primary determinant of the inspiratory load detection. The significance of these results is that inspiratory pressure generating capacity can be increased by our pressure threshold training and this increase in respiratory muscle strength increases the ability of pulmonary patients to compensate for increased respiratory load and modulates the threshold for detection of changes in pulmonary mechanics.     

医学生沟通能力标准化和个体化培养模式构建

医学生沟通项目正日益向正式的沟通课程之外延伸,并整合到实习医师、住院医师培训项目以及其他床旁或门诊教学中。医学生沟通能力的标准化、个体化的培养,有助于医学生建立良好的医患沟通模式,保持健康、和谐的医患关系。     

Effects of Individualized Centrifugation Training on Orthostatic Tolerance in Men and Women

AimsExposure to artificial gravity (AG) at different G loads and durations on human centrifuges has been shown to improve orthostatic tolerance in men. However, the effects on women and of an individual-specific AG training protocol on tolerance are not known.MethodsWe examined the effects of 90 minutes of AG vs. 90 minutes of supine rest on the orthostatic tolerance limit (OTL), using head up tilt and lower body negative pressure until presyncope of 7 men and 5 women. Subjects were placed in the centrifuge nacelle while instrumented and after one-hour they underwent either: 1) AG exposure (90 minutes) in supine position [protocol 1, artificial gravity exposure], or 2) lay supine on the centrifuge for 90 minutes in supine position without AG exposure [protocol 2, control]. The AG training protocol was individualized, by first determining each subject’s maximum tolerable G load, and then exposing them to 45 minutes of ramp training at sub-presyncopal levels.ResultsBoth sexes had improved OTL (14 minutes vs 11 minutes, p < 0.0019) following AG exposure. When cardiovascular (CV) variables at presyncope in the control test were compared with the CV variables at the same tilt-test time (isotime) during post-centrifuge, higher blood pressure, stroke volume and cardiac output and similar heart rates and peripheral resistance were found post-centrifuge.ConclusionsThese data suggest a better-maintained central circulating blood volume post-centrifugation across gender and provide an integrated insight into mechanisms of blood pressure regulation and the possible implementation of in-flight AG countermeasure profiles during spaceflights.     

Feasibility of a Combined Aerobic and Strength Training Program and Its Effects on Cognitive and Physical Function in Institutionalized Dementia Patients. A Pilot Study

Objectives

We examined the feasibility of a combined aerobic and strength training program in institutionalized dementia patients and studied the effects on cognitive and physical function.

Methods

Thirty-three patients with dementia, recruited from one nursing home, participated in this non-randomized pilot study (25 women; age = 85.2±4.9 years; Mini Mental State Examination = 16.8±4.0). In phase 1 of the study, seventeen patients in the Exercise group (EG) received a combined aerobic and strength training program for six weeks, five times per week, 30 minutes per session, in an individually supervised format and successfully concluded the pre and posttests. In phase 2 of the study, sixteen patients in the Social group (SG) received social visits at the same frequency, duration, and format and successfully concluded the pre and posttests.

Results

Indices of feasibility showed that the recruitment and adherence rate, respectively were 46.2% and 86.3%. All EG patients completed the exercise program according to protocol without adverse events. After the six-week program, no significant differences on cognitive function tests were found between the EG and SG. There was a moderate effect size in favor for the EG for the Visual Memory Span Forward; a visual attention test. There were significant differences between groups in favor for the EG with moderate to large effects for the physical tests Walking Speed (p = .003), Six-Minute Walk Test (p = .031), and isometric quadriceps strength (p = .012).

Conclusions

The present pilot study showed that it is feasible to conduct a combined aerobic and strength training program in institutionalized patients with dementia. The selective cognitive visual attention improvements and more robust changes in motor function in favor of EG vs. SG could serve as a basis for large randomized clinical trials.

Trial Registration

trialregister.nl 1230     

Critical Loads Changing with Time

The critical load is the maximal rate of contaminant addition that, over time, will result in environmental concentrations that do not exceed the highest acceptable concentration (i.e., the critical limit). Computationally, critical loads depend solely on critical limits and the expected rates at which contaminants are lost from the environmental media of concern. Losses include processes such as flushing (water bodies) or leaching (soils), sequestration in sediment, volatilization, and crop removal. A significant challenge is that loss rates will vary with time, especially in response to processes such as climate change. How should regulators deal with these changes with time? This Perspective compares the implications of three options where conditions are: (1) fixed to represent the present, (2) variable with no trend over time, and (3) variable with systematic trends (monotonic and cyclical) over time, and a fourth option using stochastic (probabilistic) evaluation of all plausible future conditions. Soil concentrations over 250 years were computed for each option. As expected, conditions that vary systematically with time can drastically change estimates of environmental concentration, and hence critical loads. However, if it is assumed that regulators periodically revisit critical load estimates taking into account changing conditions, long-term objectives can be achieved. One approach to changing conditions is to stochastically create a family of possible time series of conditions and outcomes. In the example developed here, the range of outcomes from the stochastic treatment encompassed those of the various time-series calculations. The regulatory implications of these findings are discussed.     

Implementation of Motor Imagery during Specific Aerobic Training Session in Young Tennis Players

The aim of this study was to investigate the effects of implementing motor imagery (MI) during specific tennis high intensity intermittent training (HIIT) sessions on groundstroke performance in young elite tennis players. Stroke accuracy and ball velocity of forehand and backhand drives were evaluated in ten young tennis players, immediately before and after having randomly performed two HIIT sessions. One session included MI exercises during the recovery phases, while the other included verbal encouragements for physical efforts and served as control condition. Results revealed that similar cardiac demand was observed during both sessions, while implementing MI maintained groundstroke accuracy. Embedding MI during HIIT enabled the development of physical fitness and the preservation of stroke performance. These findings bring new insight to tennis and conditioning coaches in order to fulfil the benefits of specific playing HIIT sessions, and therefore to optimise the training time.