Exercise Task Research Articles

Impaired vagal adaptation to an exercise task in women with gestational diabetes mellitus versus women with uncomplicated pregnancies.

Gestational diabetes mellitus (GDM) is associated with an increased risk for maternal and fetal complications. Patients with GDM have an increased cardiovascular risk in later life. The aim of this study was to investigate cardiac autonomic nervous system (ANS) function at rest and during exercise in women with GDM vs. women with uncomplicated pregnancies. Thirty-six normotensive pregnant women (21 with GDM and 15 age- and parity-matched women with an uncomplicated pregnancy) were enrolled in this case-control study. Continuous beat-by-beat blood pressure (BP) measurements were recorded during rest, intermittent handgrip exercise, and recovery (via photoplethysmography, Finapres®). Heart rate variability (HRV) (Kubios®) was used for the assessment of autonomic nervous system function. The groups were similar in age, gestational week, and handgrip strength. At rest, no differences in HRV indices [root mean square of successive differences (RMSSD), standard deviation Poincaré plot 1, and 2 (SD1, SD2), SD2/SD1 ratio] were detected between women with GDM and women with an uncomplicated pregnancy. However, during exercise, a different pattern in the HRV responses was detected: in the control group, RMSSD and SD1 (indices of parasympathetic function) significantly decreased (p < 0.001) during handgrip exercise and returned to baseline during recovery. In contrast, in GDM, the above HRV indices remained unaltered throughout the protocol. Normotensive women with GDM present impaired parasympathetic system ability to adapt to an exercise stimulus, as suggested by the blunted sensitivity in RMSSD and SD1. This finding suggests early alterations in ANS may exist in women with GDM, even when no differences are detected in resting conditions.

Sleep Deprivation Adversely Impacts Resident Performance for Simulated Arthroscopy

PurposeThe purpose of the study was to assess the performance of residents in orthopaedics before and after a 24-hour shift on a shoulder arthroscopy simulator. The primary study endpoint was an overall performance score (OPS) generated by the simulator.MethodsA prospective, comparative study of 120 simulator trials by 10 resident junior surgeons was performed in our university hospital’s simulation center between May and November 2018. To avoid memorization bias, all participants performed the same exercise 10 times on a VirtaMed ArthroS simulator prior to the study. Each resident’s performance (the OPS, the operating time, the proportion of procedures with iatrogenic lesions, the camera path length and the hook path length) in two different simulated arthroscopy exercise tasks was assessed once before and once after a 24-hour shift. This sequence was performed three times during the semester, and the change over time in performance was also evaluated.ResultsThe OPS was significantly lower after the night shift (P = 0.035 for the first exercise, and P = 0.025 for the second).ConclusionIn a group of previously trained resident junior surgeons, overall performance with an arthroscopy simulator was significantly worse after a 24-hour shift. The study of secondary parameters of the OPS and the subgroup analysis based on the sleep time and Epworth score vary depending on the type of exercise performed arthroscopically. However, the use of a simulator after a night shift did not prevent the trainee from improving his/her level of performance over time.Level of EvidenceII, a prospective, comparative study

Electromyographic Analysis of Gluteus Medius Activity in People with Non-Specific Chronic Low Back Pain Compared to Healthy Controls

Background and Objectives: The functioning of the hip and trunk muscles has an effect on low backregion. Gluteus medius (Gmed) being the primary hip abductor plays a significant role in maintaining thestability of the pelvis. Despite the significance, this muscle activity is least addressed and is also thoughtto be one among the major causes of pain in the low back. The aim of the study was to compare theactivity of Gmed in non-specific chronic low back pain (NSCLBP) and healthy individuals using SurfaceElectromyography (SEMG).Methods: 506 subjects were screened, of which 200 subjects were selected. Group A: NSCLBP (n=100)and GROUP B: Healthy controls (n=100). Both groups were instructed to perform maximum voluntarycontractions. The mean root mean square (RMS) value of Gmed muscle activity for the exercise task wasrecorded and analyzed using SEMG.Results: The results demonstrated that the mean RMS value of the right Gmed muscle activity for GROUPA was lesser (53.00 ± 24.81) than GROUP B (87.9 ± 37.47). The mean RMS value of the left Gmed activitywas also lesser for GROUP A (55.99 ± 27.21) compared to GROUP B (89.72 ± 39.83). The difference inmeans between the two groups showed highly significant outcome (P<0.001).Conclusion: The study concluded that the muscle activity of Gmed between the groups was lesser in GroupA compared to Group B indicating differential activation of the muscle in people with NSCLBP. However,there was no significant difference in mean RMS value of the right and left Gmed muscle activity whencompared within the groups respectively.

Effects of a Community-Based Familiarization Intervention on Independent Performance of Resistance-Training Exercise Tasks by Adults With Intellectual Disability.

Adults with intellectual disability (ID) have significantly lower levels of fitness compared to the general population. The study examined the effects of a multicomponent familiarization intervention, consisting of a visual activity schedule and a video-enhanced system of least-to-most prompting, both displayed via an iPad, on the acquisition of resistance-training exercise tasks by adults with ID, aged 18-44 years, in a community fitness center. Twelve participants were randomly allocated to an experimental group (EG) and 12 to an active control group (CG). ANOVA revealed EG correctly and independently performed a significantly greater number of steps of four resistance-training exercise tasks compared with CG, relative to preintervention levels (p < .01). The intervention was effective in promoting functional performance of resistance-training exercise tasks among adults with ID.

Identifying sex differences in neuromuscular fatigue: the challenge of normalizing exercise intensity and interpreting the results between populations.

Identifying sex differences in neuromuscular fatigue: the challenge of normalizing exercise intensity and interpreting the results between populations.

284 Cognitive Deficits due to Insufficient Sleep are Mitigated Following Strenuous Physical Exertion in Firefighters

Abstract Introduction Insufficient sleep impairs cognitive function which results in costly errors. Firefighter shifts regularly exceed 24-hrs with little to no sleep. Nevertheless, firefighters must maintain and flexibly shift attention in high-pressure scenarios. Firefighters also engage in strenuous physical exertion during fire suppression activities. However, it is unclear whether physical exertion acts as another stressor, exasperating cognitive deficits due to insufficient sleep, or whether physical exertion enhances arousal to reduce cognitive deficits. Moreover, the effects of physical exertion may depend on the type of cognitive process and extent of sleep loss. We examined the effect of physical exertion on vigilant attention and task-switching in firefighters who underwent sleep-deprivation or sleep-disruption. Methods Participants were 17 healthy young adult males who participated in a within-subjects crossover design with three experimental lab visits: sleep-deprivation, sleep-disruption (woken 3 times for 60-min each), and normal sleep. The next day, participants completed a 50-min treadmill exercise task in a heated room in firefighter protective clothing. Participants completed a vigilant attention task (Psychomotor Vigilance Task, PVT) and a task-switching task five to nine times each visit. The five timepoints of interest–before and after the sleep manipulation night, before and after the treadmill exercise task, and recovery (approximately 180-min following exercise)–were examined using linear mixed effects models. Results We analyzed lapses (reaction times [RT]&amp;gt;500ms) on the PVT and switch-trial RT and accuracy on the task-switching task for sleep-deprivation and sleep-disruption conditions relative to normal sleep. Sleep-disruption, p=.001, and sleep-deprivation, p&amp;lt;.001, increased lapses. Sleep-disruption increased switch-trial RT, p=.01, and sleep-deprivation reduced switch-trial accuracy, p=.01. Only switch-trial accuracy improved immediately after the treadmill exercise task and only for the sleep-deprivation condition, p=.01. During recovery, lapses lessened for the sleep-deprivation condition, p=.049, and switch-trial accuracy improved for both sleep-deprivation, p=.01, and sleep-disruption conditions, p=.049. Conclusion Physical exertion reduced task-switching and attentional deficits caused by insufficient sleep, with more benefits observed during recovery. We found no evidence for performance decrements due to physical exertion. Physical exertion may interact with the extent of sleep loss–primarily benefitting performance under conditions of total sleep-deprivation. Support (if any) DSF Charitable Foundation and University of Pittsburgh Clinical and Translational Science Institute UL1TR001857.

A Fast‐Start Pacing Strategy Does Not Improve Locomotor Fatigue Dynamics But Does Improve Supra‐Critical Power Work Capacity

Tolerance for high-intensity constant power exercise is dictated by the hyperbolic relationship between power and duration. This relationship is defined by two parameters: the asymptote, termed critical power, and the curvature constant (W′). Critical power distinguishes predictable tolerance to high-intensity work from power outputs resulting in unpredictable exercise tolerance. The amount of work that can be completed above critical power is W′. Interestingly, the pacing strategy for which the participant expends W' affects exercise tolerance in short bouts. However, these improvements seem not to persist during exercise bouts 6 min or longer. Purported mechanisms for this modulation in tolerance are speeding/slowing of oxidative metabolism. One result of speeded kinetics of metabolism could be the preservation of voluntary locomotor power. Objective To measure locomotor muscle fatigue dynamics and exercise tolerance during a fast-start pacing strategy compared to a constant power task. Methods Volunteers (N=15, 27±4yr, 176±7cm, 77±12kg) completed constant and fast-start exercise tasks to the limit of tolerance above critical power. Maximal isokinetic power was measured throughout as an index of locomotor fatigue. Results Compared to constant power pacing, a fast-start pacing strategy resulted in augmented tolerance to supra-critical power exercise of (CI95 23, 79 s). Tolerance to constant power exercise was reproducible and was not different before and after the fast-start strategy bout. The decline in maximal isokinetic power was not different during constant power and fast-start pacing strategies, nor was there an interaction of pacing strategy and time (F[5, 168]=0.5, p=0.75). Maximal isokinetic power was lower during the fast-start strategy vs constant power when the data were normalized to baseline isokinetic power (F[1,168]=6.2, p=0.01). However, no interaction of pacing strategy and time was present (F[5,168]=0.39, p=0.85). Conclusions While fast-start pacing improved exercise tolerance and augmented the supra-critical power work tolerance, the dynamics of locomotor fatigue were not different between conditions. Interestingly, our data argue against a fixed volume of work (W') above critical power and lend more evidence that W' is a result of a complex conflation of fatigue-related processes rather than a simple work capacity.

Anticipation of and response to exercise in adolescents with CFS: An experimental study

BackgroundUsing a laboratory-based exercise task, this study investigated objective exercise performance as well as expectations, anxiety and perceived task performance ratings in adolescents with CFS compared to healthy controls and illness controls. MethodTrials of a sit-stand exercise task (SST) were undertaken (CFS: n = 61, asthma (AS): n = 31, healthy adolescents (HC): n = 78). Adolescents rated their expectations, pre- and post-task anxiety, and perceived task difficulty. Their parents independently rated their performance expectations of their child. ResultsThe CFS group took significantly longer to complete the SST than the AS group (MD 3.71, 95% CI [2.41, 5.01] p < .001) and HC (MD 3.61, 95% CI [2.41, 4.81], p < .001). Adolescents with CFS had lower expectations for their performance on the exercise task than AS participants (MD -11.79, 95% CI [−22.17, −1.42] p = .022) and HC (MD -15.08, 95% CI [−23.01, −7.14] p < .001). They rated their perceived exertion as significantly greater than AS (MD 3.04, 95% CI [1.86, 4.21] p < .001) and HC (MD 2.98, 95% CI [1.99, 3.98], p < .001). The CFS group reported greater anxiety pre-task than AS (MD 14.11, 95% CI [5.57, 22.65] p < .001) and HC (MD 11.19, 95% CI [2.64, 19.75], p. = 007). Parental group differences showed similar patterns to the adolescents’'. ConclusionsLower expectations and greater anxiety regarding exercise may reflect learning from previous difficult experiences which could impact future exercise performance. Further examination of pre-exercise expectations and post-exercise appraisals could improve our understanding of the mechanisms by which fatigue is maintained.

Attenuation of the Köhler Effect in Racially Dissimilar Partnered Exercise Reversed Using Team Identity Strategy.

The authors describe two research experiments exploring the influence of race on the Köhler motivation gain effect with exercise tasks. Experiment 1 tested whether partner racial dissimilarity affects individual performance. Experiment 2 created a team identity recategorization intervention to potentially counter the influence on performance observed in Experiment 1. White male participants were partnered with either a Black or Asian partner (Experiment 1) or with a Black partner utilizing team names and shirt colors as a team identity recategorization strategy (Experiment 2). Racially dissimilar dyads completed two sets of abdominal plank exercises with a Köhler conjunctive task paradigm (stronger partner; team performance outcome dependent upon the weaker-ability participant's performance). The results of Experiment 1 suggest attenuation of the previously successful group motivation gain effect in the racially dissimilar condition. The simple recategorization strategy utilized in Experiment 2 appeared to reverse motivation losses under conjunctive-task conditions in racially dissimilar exercise dyads.

Developing Educational Games for Preschool Children to Improve Dietary Choices and Exercise Capacity

This article describes the processes used to develop two different types of games used to improve the consumption of healthful foods and increase exercise in preschool Hispanic populations. They were created to meet criteria for effectiveness: age and culturally appropriate, fun, and foster family participation. The first, a pictorial bilingual food bingo game, emphasized vegetable and water consumption and the limitation of sugar-sweetened beverages. A population was selected to study the effectiveness in changing dietary habits, and we were able to show a significantly improved consumption of vegetables at home after using the game during the school year. Next, we developed bilingual video games used to teach nutrition and enhance exercise. The animal characters and narrative were created to allow immersion. The concept was that the animals needed the children’s help to obtain food, exercise tasks were assigned, and nutritional foods were discussed. Focus groups were reviewed for the effectiveness of the concept, ease of usability, and appropriateness for the target audience. The videos were tested in a summer session, and teachers concluded that after two viewings the children enhanced their exercise, bonded to the animals, and were answering the nutrition questions correctly.

Characteristics of the Electrophysiological Properties of Neuromuscular Motor Units and Its Adaptive Strategy Response in Lower Extremity Muscles for Seniors with Pre-Sarcopenia: A Preliminary Study.

Older adults with sarcopenia, which is an aging-related phenomenon of muscle mass loss, usually suffer from decreases in both strength and functional performance. However, the causality between function loss and physiological changes is unclear. This study aimed to explore the motor unit characteristics of the neurological factors between normal subjects and those with sarcopenia. Five risk-sarcopenia (age: 66.20 ± 4.44), five healthy (age: 69.00 ± 2.35), and twelve young (age: 21.33 ± 1.15) participants were selected. Each participant performed knee extension exercises at a 50% level of maximal voluntary isometric contraction. Next, electromyogram (EMG) signals were collected, and information on each parameter—e.g., motor unit number, recruitment threshold, the slope of the mean firing rate to recruitment threshold, y-intercept, firing rate per unit force, and mean motor unit firing rate (MFR)—was extracted to analyze muscle fiber discrimination (MFD). Meanwhile, force variance was used to observe the stability between two muscle groups. The results suggested that there was no difference between the three groups for motor unit number, recruitment threshold, y-intercept, mean firing rate, and motor unit discrimination (p > 0.05). However, the slope of MFR and firing rate per unit force in the risk-sarcopenia group were significantly higher than in the young group (p < 0.05). Regarding muscle performance, the force variance in the non-sarcopenia group was significantly higher than the young group (p < 0.05), while the risk-sarcopenia group showed a higher trend than the young group. This study demonstrated some neuromuscular characters between sarcopenia and healthy elderly and young people when performing the same level of leg exercise tasks. This difference may provide some hints for discovering aging-related strength and function loss. Future studies should consider combining the in vivo measurement of muscle fiber type to clarify whether this EMG difference is related to the loss of muscle strength or mass before recruiting symptomatic elderly participants for further investigation.

Pacing behaviour of middle-long distance running & race-walking athletes at the IAAF U18 and U20 World Championship finals

ABSTRACT The current study analysed the pacing behaviour of athletes competing in the middle-long track event finals of the IAAF Under 18 and Under 20 World Championships between 2015 and 2018. Official finishing times, 1000-m split times and positioning data of 116 female and 153 male athletes, competing in the middle-long distance running (3000 m, 5000 m and 10,000 m) and race walking (5000 m and 10,000 m) events, were gathered. Repeated measures analysis of variance, with 1000-m speed as within-subjects factor and final ranking (medallist, Top 8 or Top 12, rest of the field) as between-subjects factor, was performed to compare the pacing behaviour between athletes. Positioning of the athletes was analysed by Kendall tau-b (Tb) correlation between the intermediate position and final position. Overall, medallists increased their speed throughout a race, with the exception of the 5000 m running event, in which a parabolic pacing behaviour was exhibited. The 1000-m segment in which a significant (P > 0.05) difference in speed was exhibited between differently ranked athletes coincided with a strong (Tb > 0.7) correlation between intermediate and final positioning. These combined results point towards a separation between the athletes during the race, as the Top 8 or Top 12 and the rest of the field are unable to match the speed of the medallists. The distance, discipline, sex, age category and behaviour of competitors all influence the pacing behaviour of young track athletes during international level competition, emphasising the importance and complexity of developing adequate pacing behaviour in track athletes. Highlights The distribution of effort over an exercise task (i.e. pacing) is an important factor in endurance exercise competition. The pacing behaviour of athletes is determined by many aspects, such as the biomechanical characteristics of the task, the exercise environment and the age of the athlete Sport specific competition data from youth athlete sports events can provide insight into the pacing behaviour of developing athletes. These insights could assist in the optimalisation of the development of pacing behaviour of young athletes in the future. The current study analysed the 1000-m split times and positioning data of athletes competing in the running (3000 m, 5000 m and 10,000) and racewalking (5000 m and 10,000m) finals of the U18 and U20 IAAF world-championship. The difference in final ranking impacted the pacing behaviour of the athletes, with the medallists increasing their speed throughout the race and the other athletes separating from the medallists either early (rest of field) or later in the race (Top 8 or Top 12 athletes).

Mental fatigue, anticipated effort, and subjective valuations of exercising predict choice to exercise or not: A mixed-methods study

ObjectivesThis study examined the effects of mental fatigue on people's decisions to engage in an acute bout of exercise quantitatively, through a sequentially mediated pathway consisting of perceived effort and benefit vs. cost valuations and qualitatively, using exit interviews to survey the conscious reasoning behind participants' choices. DesignMixed methods, randomized, experimenter blind to group. MethodParticipants (N = 84, Mage = 19.07 ± 1.86 years) completed either a high cognitive demand (incongruent Stroop) task or low cognitive demand (documentary viewing) task for 12 min. Before and after the cognitive task, participants rated their anticipated effort and subjective evaluations (benefits and costs) of engaging in a 20-min moderate-to-vigorous intensity exercise task. After completing the latter ratings, participants chose between the exercise task or a non-exercise task (seated “free time” and use of smartphone or computer). Participants were led to believe they would actually engage in the task; however, once their choice was made, they were not required to complete the task but were invited to complete a semi-structured interview to probe the reasoning behind their choice. ResultsSerial mediation analyses revealed a significant indirect effect from mental fatigue to choice through perceived effort and benefit vs. cost valuations (95% C.I. = −0.01 to −0.0004). Qualitative data, organized by categories based on group/choice pairings, yielded twelve unique codes explaining how the cognitive tasks affected choice. ConclusionsResults demonstrate mental fatigue alters decision-making through a sequentially mediated process including subjective perceptions of effort, benefits, and costs. Interview responses also highlight the individual-level consequences of completing cognitively demanding and non-demanding tasks on effort-based decision-making. Future research should explore additional feeling states as they relate to people's choices to engage in exercise or sedentary behaviors.

The Effect of a Brief-Mindfulness Intervention on Psychophysiological Exertion and Flow-State Among Sedentary Adults.

Mindfulness-acceptance commitment interventions in sport and exercise contexts have been helpful to increasing a positive psycho-physiological state among competitive athletes and recreational exercise participants. In the current study, we sought to extend research in this area by identifying the effect of a brief-mindfulness intervention on psychophysiological functioning among healthy but sedentary young adults. Our mixed gender sample (n = 42) of inactive individuals performed a brief cycling task without training (control condition) followed by task completion with brief mindfulness training (15-minute audio engagement with mindfulness techniques and specific present moment 'anchors'). We found that participants self-reported more accurate ratings of perceived exertion (i.e., self-ratings better matched actual physiological indices of exertion) following the mindfulness intervention, suggesting that mindfulness techniques can increase bodily awareness. Better body awareness may be useful to helping sedentary participants appreciate physiological changes experienced through exercise. The mindfulness manipulation also increased participants' absorption into the activity, suggesting greater attentiveness to the exercise task with less distraction from irrelevant external and internal cues. In sum, mindfulness may be a complementary psychological training tool for inactive, sedentary young adults attempting to re-engage with exercise. We provide recommendations for future research.

Elevated peripheral inflammation is associated with attenuated striatal reward anticipation in major depressive disorder

BackgroundMajor depressive disorder (MDD) is the leading cause of years lived with disability worldwide, and up to 40% of individuals with MDD do not respond to current treatments. Studies suggest that peripheral inflammation plays an important role in the striatal mesolimbic dopamine pathway and corticostriatal reward circuitry in MDD. Although MDD patients show blunted striatal responses to reward, the link between degree of inflammation and attenuation of reward processing is unclear. We investigated whether MDD patients with elevated peripheral inflammation exhibit attenuated reward responses to enhance our understanding of MDD pathophysiology and develop more effective treatments for current non-responders. MethodsMDD subjects varying on serum C-reactive protein (CRP) concentrations (MDD-High CRP, >3 mg/L, n = 44; MDD-Low CRP, <3 mg/L, n = 44) and healthy comparisons (HC, n = 44) completed a monetary incentive delay (MID) task and provided blood samples to measure inflammation-related markers. MDD-High and MDD-Low were propensity score-matched on age, sex, body mass index (BMI), smoking status, exercise and MID task head motion. Percent change in blood oxygen level-dependent (BOLD) signal during anticipation of wins and losses was extracted from bilateral nucleus accumbens, dorsal caudate and dorsolateral putamen regions of interest (ROIs). A linear mixed-effects model was used to test group (MDD-High, MDD-Low and HC), condition (large-win, small-win and no win), and their interaction for these ROIs as well as whole-brain voxelwise data. Analyses also tested group differences in inflammatory mediators. Correlations were used to explore the relationship between inflammatory mediators and brain regions showing differences between MDD-High and MDD-Low. ResultsMDD-High exhibited: (a) lower BOLD signal change in dorsal caudate, thalamus, left insula and left precuneus during anticipation of small wins than MDD-Low; and (b) higher serum soluble intercellular adhesion molecule 1 (sICAM-1) and interleukin 6 (IL-6) concentrations than MDD-Low and HC. MDD as a whole, regardless of CRP-based inflammation, exhibited: (a) lower precuneus BOLD signal change to large wins than HC; and (b) higher Interleukin 1 receptor antagonist (IL-1ra), macrophage-derived chemokine (MDC) and macrophage inflammatory protein-1 alpha (MIP-1α) concentrations than HC. Higher serum sICAM-1 concentrations were associated with lower caudate BOLD signal change to small wins only within the MDD-High group. ConclusionWithin MDD patients, high inflammation (CRP, sICAM-1) was linked to reduced striatal activation recruited to discriminate intermediate reward magnitudes. These findings support an association between levels of peripheral inflammation and the degree of reward-related activation in individuals with MDD. Registration of clinical trialsThe ClinicalTrials.gov identifier for the clinical protocol associated with data published in this current paper is NCT02450240, “Latent Structure of Multi-level Assessments and Predictors of Outcomes in Psychiatric Disorders.”

Exercise-induced muscle damage: mechanism, assessment and nutritional factors to accelerate recovery.

There have been a multitude of reviews written on exercise-induced muscle damage (EIMD) and recovery. EIMD is a complex area of study as there are a host of factors such as sex, age, nutrition, fitness level, genetics and familiarity with exercise task, which influence the magnitude of performance decrement and the time course of recovery following EIMD. In addition, many reviews on recovery from exercise have ranged from the impact of nutritional strategies and recovery modalities, to complex mechanistic examination of various immune and endocrine signaling molecules. No one review can adequately address this broad array of study. Thus, in this present review, we aim to examine EIMD emanating from both endurance exercise and resistance exercise training in recreational and competitive athletes and shed light on nutritional strategies that can enhance and accelerate recovery following EIMD. In addition, the evaluation of EIMD and recovery from exercise is often complicated and conclusions often depend of the specific mode of assessment. As such, the focus of this review is also directed at the available techniques used to assess EIMD.

Submaximal Exercise Task Post Clinical Balance in COPD Patients and its Correlation with Quadriceps Girth, Body Mass Index and Disease Severity

Purpose: To study and compare the effect of submaximal exercise on static and dynamic balance in patientswith severe and moderate chronic obstructive pulmonary disease (COPD) and correlation of the balanceimpairments with disease severity, quadriceps girth and body mass index (BMI).Methods: A sample of convenience of 45 middle aged participants (mean age 53.47 ± SD 4.775), including15 with severe COPD, 15 with moderate COPD who were not undergoing pulmonary rehabilitation programand 15 healthy controls were included. The subjects performed Timed Up and Go Test (TUG) for dynamicbalance and quiet standing to assess postural sway using sway meter with eyes closed and opened in narrow,semi tandem and tandem stance for 30 seconds. The balance variables were then correlated to forcedexpiratory volume in one second (FEV1), quadriceps girth and body mass index. Significance was set atalpha less than 0.05.Results: when compared to healthy controls, significant differences were found in postural sway in all thestances in severe COPD patients, and in semi tandem and tandem stances in moderate COPD patients. TUGtest significantly differed in both severe and moderate COPD (p=0.0001) and no difference between severeand moderate COPD TUG test was found. Moderate negative correlation was found between FEV1 andpostural away in few stances whereas no correlation was found with quadriceps girth and BMI of COPDpatients.Conclusion: Static as well as dynamic balance are affected in COPD patients with postural sway affectedmore in severe COPD than moderate COPD leading to functional disability and risk of falls which increaseswith increase in age. Balance alterations can be moderately correlated to FEV1.

Effects of isometric contraction of the quadriceps on the hardness and blood flow in the infrapatellar fat pad.

[Purpose] This study aimed to clarify the influence of the isometric contraction of the quadriceps (ICQ) with low intensity on the circulation in the infrapatellar fat pad (IFP). [Participants and Methods] The participants were 7 males and 5 females, with an average age of 21.5 ± 1.4 years. IFP hardness was measured using shear wave ultrasound elastography and Biodex. Tissue oxygenation was measured via near-infrared spectroscopy using oxygenated hemoglobin (O2Hb), deoxygenated hemoglobin (HHb), and total hemoglobin (cHb) as indices. The mean values were calculated for three periods: 1 min of rest immediately before the exercise task (before ICQ), the lower limit of the 10 sets during the exercise task (during ICQ), and 3–4 min after the exercise task (after ICQ). IFP hardness was compared between resting conditions and ICQ, and tissue oxygenation was compared before, during, and after ICQ. [Results] ICQ significantly increased IFP hardness. Tissue hemoglobin, O2Hb, and cHb decreased significantly during ICQ and increased after ICQ compared to that before ICQ. HHb decreased during ICQ and recovered significantly after ICQ. [Conclusion] In healthy participants, low-intensity ICQ increases the hardness and oxygenation of the IFP. This study may partly explain the unknown pain relief mechanism of exercise therapy.

The effectiveness of online physical education classes focusing on self-monitoring of daily life and exercise tasks

The effectiveness of online physical education classes focusing on self-monitoring of daily life and exercise tasks

Dynamic balance ability in single-leg drop jump landing in junior female athletes after shin splints-assessment from a preventive perspective.

[Purpose] To develop assessment/rehabilitation indices for prevention of chronic and recurrent shin splint injuries among sport athletes, we analyzed the plantar center of pressure trajectories after drop-jump landing on one leg, and compared the foot function on the injured and healthy sides. [Participants and Methods] The participants were 10 female athletes who received consultation at our facility due to shin splints of the lower leg. The exercise task was the “single-leg drop jump landing test”, in which the participants maintained a static posture on one leg for 8 s after landing. Using the collected data, the peak value of the vertical component of the floor-reaction force at the landing and the rectangular areas at 20–200 ms and 1–5 s after landing were calculated and compared between the healthy and affected sides. [Results] The peak value of the vertical component and the rectangular area at 20–200-ms were significantly larger on the affected side. However, the value for the 1–5-s rectangular area was significantly larger on the healthy side. [Conclusion] The feedforward function may have been reduced on the affected side in comparison with that on the healthy side, and the reduction in dynamic balance early after landing may have increased the influence of the non-vertical component. The 1–5-s rectangular area was smaller on the affected side than that on the healthy side, suggesting that the feedback function excessively worked on the affected side and caused immobility by excessively locking the joint in single-leg balance and reducing body sway.