The Influence of Altered-Gravity on Bimanual Coordination: Retention and Transfer

Many of the activities associated with spaceflight require individuals to coordinate actions between the limbs (e.g., controlling a rover, landing a spacecraft). However, research investigating the influence of gravity on bimanual coordination has been limited. The current experiment was designed to determine an individual’s ability to adapt to altered-gravity when performing a complex bimanual force coordination task, and to identify constraints that influence coordination dynamics in altered-gravity. A tilt table was used to simulate gravity on Earth [90° head-up tilt (HUT)] and microgravity [6° head-down tilt (HDT)]. Right limb dominant participants (N = 12) were required to produce 1:1 in-phase and 1:2 multi-frequency force patterns. Lissajous information was provided to guide performance. Participants performed 14, 20 s trials at 90° HUT (Earth). Following a 30-min rest period, participants performed, for each coordination pattern, two retention trials (Earth) followed by two transfer trials in simulated microgravity (6° HDT). Results indicated that participants were able to transfer their training performance during the Earth condition to the microgravity condition with no additional training. No differences between gravity conditions for measures associated with timing (interpeak interval ratio, phase angle slope ratio) were observed. However, despite the effective timing of the force pulses, there were differences in measures associated with force production (peak force, STD of peak force mean force). The results of this study suggest that Lissajous displays may help counteract manual control decrements observed during microgravity. Future work should continue to explore constraints that can facilitate or interfere with bimanual control performance in altered-gravity environments.

Quantitative Analysis of Performance Recovery in Semi-Professional Football Players after the COVID-19 Forced Rest Period

This study proposes the instrumental analysis of the physiological and biomechanical adaptation of football players to a fatigue protocol during the month immediately after the COVID-19 lockdown, to get insights into fitness recovery. Eight male semi-professional football players took part in the study and filled a questionnaire about their activity during the lockdown. At the resumption of activities, the mean heart rate and covered distances during fatiguing exercises, the normalized variations of mean and maximum exerted power in the Wingate test and the Bosco test outcomes (i.e., maximum height, mean exerted power, relative strength index, leg stiffness, contact time, and flight time) were measured for one month. Questionnaires confirmed a light-intensity self-administered physical activity. A significant effect of fatigue (Wilcoxon signed-rank test p < 0.05) on measured variables was confirmed for the four weeks. The analysis of the normalized variations of the aforementioned parameters allowed the distinguishing of two behaviors: downfall in the first two weeks, and recovery in the last two weeks. Instrumental results suggest a physiological and ballistic (i.e., Bosco test outcomes) recovery after four weeks. As concerns the explosive skills, the observational data are insufficient to show complete recovery.

Multi-Parameter Physiological State Monitoring in Target Detection Under Real-World Settings

Mental state changes induced by stimuli under experimental settings or by daily events in real life affect task performance and are entwined with physical and mental health. In this study, we developed a physiological state indicator with five parameters that reflect the subject’s real-time physiological states based on online EEG signal processing. These five parameters are attention, fatigue, stress, and the brain activity shifts of the left and right hemispheres. We designed a target detection experiment modified by a cognitive attention network test for validating the effectiveness of the proposed indicator, as such conditions would better approximate a real chaotic environment. Results demonstrated that attention levels while performing the target detection task were significantly higher than during rest periods, but also exhibited a decay over time. In contrast, the fatigue level increased gradually and plateaued by the third rest period. Similar to attention levels, the stress level decreased as the experiment proceeded. These parameters are therefore shown to be highly correlated to different stages of the experiment, suggesting their usage as primary factors in passive brain-computer interfaces (BCI). In addition, the left and right brain activity indexes reveal the EEG neural modulations of the corresponding hemispheres, which set a feasible reference of activation for an active BCI control system, such as one executing motor imagery tasks. The proposed indicator is applicable to potential passive and active BCI applications for monitoring the subject’s physiological state change in real-time, along with providing a means of evaluating the associated signal quality to enhance the BCI performance.

Cardiovascular Metrics Associated With Prevention of Aging-Related Parkinsonian Signs Following Exercise Intervention in Sedentary Older Rats

Preservation of motor capabilities is vital to maintaining independent daily living throughout a person's lifespan and may mitigate aging-related parkinsonism, a progressive and prevalent motor impairment. Physically active lifestyles can mitigate aging-related motor impairment. However, the metrics of physical activity necessary for mitigating parkinsonian signs are not established. Consistent moderate intensity (~10 m/min) treadmill exercise can reverse aging-related parkinsonian signs by 20 weeks in a 2-week on, 2-week off, regimen in previously sedentary advanced middle-aged rats. In this study, we initiated treadmill exercise in sedentary 18-month-old male rats to address two questions: (1) if a rest period not longer than 1-week off exercise, with 15 exercise sessions per month, could attenuate parkinsonian signs within 2 months after exercise initiation, and the associated impact on heart rate (HR) and mean arterial pressure (MAP) and (2) if continuation of this regimen, up to 20 weeks, will be associated with continual prevention of parkinsonian signs. The intensity and frequency of treadmill exercise attenuated aging-related parkinsonian signs by 8 weeks and were maintained till 23 months old. The exercise regimen increased HR by 25% above baseline and gradually reduced pre-intervention MAP. Together, these studies indicate that a practicable frequency and intensity of exercise reduces parkinsonian sign severity commensurate with a modest increase in HR after exercise. These cardiovascular changes provide a baseline of metrics, easily measured in humans, for predictive validity that practicable exercise intensity and schedule can be initiated in previously sedentary older adults to delay the onset of aging-related parkinsonian signs.

The Effect of Circuit Resistant Training on Cardiorespiratory indices; Implication for Developing a Test Model for Soccer Players of Higher Education Institutions

The current research aimed to incorporate appropriate circuit resistant training protocol in the current literature and device that could help improve cardio-respiratory endurance of soccer players. A pre-test and post-test longitudinal research format was applied because the suggested parameters of cardiorespiratory endurance were appropriately calculated by such research designs. A sample of (n=40) healthy volunteers equally distributed into two different groups namely, an experimental group (EG) and a control group (CG). The circuit resistant training (CRT) 3 times per week with specified intensity, repetition, set and rest period continued for 06 weeks among experimental group. Results of the analyzed data revealed a significant increase in the cardiorespiratory indices (CO, SV, IRV, ERV) among the participants of experimental group (p < .05). These results tend to interpret that cardiorespiratory fitness of soccer’s players can be improved with the help of 06 week (CRT) program. Apart from this, health and physical education teachers, physiotherapists and other relevant persons can recommend CRT for lifestyles improvement.

Comparison of Effectiveness of Passive Hamstring Stretching Technique and Neurodynamic Sciatic Nerve Sliding Technique in Low Back Pain

Objective: Low back pain (LBP) is a very common health problem worldwide having global point prevalence of 9.4%. Correlations have been found between decreased length of the hamstrings and LBP. It was found that improving the flexibility of hamstrings can significantly reduce chronic LBP. This study compared the effectiveness of two techniques i.e. passive hamstring stretching technique (PHS) and neurodynamic sciatic nerve sliding technique (NDS) on hamstring flexibility and pain in non-radiating LBP patients. Methods: 26 patients between the age group of 25-45 years having non-radiating LBP were recruited in the study. Group A (n=13) were given passive hamstring stretching while Group B (n=13) performed neurodynamic sciatic nerve sliding technique under guidance of the researcher. Baseline data were obtained for hamstring length and pain before and after intervention. Pain was assessed using ‘visual analogue scale’ and hamstring length was measured using ‘passive knee extension test’. Intervention was performed on alternate days for three sessions with 48 hours rest period in between each session. Results: Data were analysed for hamstring length and pain between both the groups using ‘unpaired t’ test. NDS technique was statistically significantly more effective in improving pain (p =0.03 at 95%CI= -2.07 to -0.09). There was no statistically significant difference in the effectiveness of both techniques in improving hamstring length (p =0.08 at 95%CI= -3.4 to 0.25). Conclusions: Both the techniques are equally effective in improving hamstring length, however NDS was more effective in improving pain in low back pain patients as compared to PHS. Keywords: Low back pain; Neural sliders; Static hamstring stretch; Hamstring flexibility .

Similar Supine Heart Rate Variability Changes During 24-h Exposure to Normobaric vs. Hypobaric Hypoxia

Purpose: This study aimed to investigate the differences between normobaric (NH) and hypobaric hypoxia (HH) on supine heart rate variability (HRV) during a 24-h exposure. We hypothesized a greater decrease in parasympathetic-related parameters in HH than in NH.Methods: A pooling of original data from forty-one healthy lowland trained men was analyzed. They were exposed to altitude either in NH (FIO2 = 15.7 ± 2.0%; PB = 698 ± 25 mmHg) or HH (FIO2 = 20.9%; PB = 534 ± 42 mmHg) in a randomized order. Pulse oximeter oxygen saturation (SpO2), heart rate (HR), and supine HRV were measured during a 7-min rest period three times: before (in normobaric normoxia, NN), after 12 (H12), and 24 h (H24) of either NH or HH exposure. HRV parameters were analyzed for time- and frequency-domains.Results: SpO2 was lower in both hypoxic conditions than in NN and was higher in NH than HH at H24. Subjects showed similarly higher HR during both hypoxic conditions than in NN. No difference in HRV parameters was found between NH and HH at any time. The natural logarithm of root mean square of the successive differences (LnRMSSD) and the high frequency spectral power (HF), which reflect parasympathetic activity, decreased similarly in NH and HH when compared to NN.Conclusion: Despite SpO2 differences, changes in supine HRV parameters during 24-h exposure were similar between NH and HH conditions indicating a similar decrease in parasympathetic activity. Therefore, HRV can be analyzed similarly in NH and HH conditions.

ENERGY EXPENDITURE IN HIIT WHOLE BODY ASSOCIATED WITH ELECTROMYOSTIMULATION

ABSTRACT Introduction: The use of whole body electromyostimulation (WB-EMS) has been shown to be an efficient method for inducing significant improvements in muscle strength and performance outcomes. Hypothetically, WB-EMS had been considered an enhancer of energy expenditure in the session, but this remains unclear. Objective: In view of the lack of information, this study aims to evaluate the energy expenditure of WB-EMS associated with whole body High-Intensity Interval Training (HIIT). Methods: Fourteen male participants were submitted into two randomized exercise sessions: HIIT (whole body weight exercises without WB-EMS) and HIIT+WB-EMS (whole body weight exercises associated with WB-EMS). For both exercise conditions, the subjects performed whole body HIIT according to the following protocol: 3 minutes of warm-up followed by 4 exercises (30 seconds of stimulus) organized in 2 blocks, with 3 sets in each exercise, a rest period of 15 seconds between sets, and 180 seconds between blocks. The following exercises were performed: jumping jacks, squat and thrusts, burpees, and spider plank. Results: Significant differences were found in the absolute VO2 (HIIT:2.18±0.34, HIIT+WB-EMS:2.32±0.36 L.min−1) and relative VO2 (HIIT:26.30±3.77, HIIT+WB-EMS:28.02± 3.74 ml.kg.min−1), MET (HIIT:7.51±1.07, HIIT+WB-EMS:8.00±1.07), lactate concentration (HIIT:11.59±2.16, HIIT+WB-EMS: 12.64±1.99 mmol.L−1) and total energy expenditure (HIIT: 249.6± 45.04 Kcal, HIIT+ WB-EMS: 268.9±40.67 Kcal; 7.46 ± 5.31%). Conclusion: Our data indicate that the use of WB-EMS associated with HIIT generated a slightly higher metabolic demand than that of the control. However, the absolute differences do not allow us to indicate the superiority of WB-EMS, and future trials should be designed to determine the long-term effects.

Comparison of the effectiveness of captopril and olmesartan in hypertensive patients

Purpose: Hypertensive conditions are situations that require immediate intervention in emergency services. Captopril is one of the most commonly used drugs in patients presenting to emergency departments with high blood pressure. In this study; we aimed to find an answer to the question of whether orally administered olmesartan could be an alternative to captopril in urgent hypertensive situations. Material and Method: In this study, blood pressure measurements were made after a 5-minute rest period in patients who presented to the emergency department of our hospital with the diagnosis of hypertension. Patients with a blood pressure of 180/100 mmHg and above and no signs of end-organ damage were followed up. Forty patients were given sublingual captopril 25 mg, and the other 40 patients were given 40 mg of olmesartan, and they were allowed to swallow the drug with some water. Afterward, the patients were followed for 3 hours (with blood pressure and pulse measurements), and their blood pressure was measured and recorded at five-minute intervals. Results: The mean age of the patients receiving captopril was 60.70±11.43 years, and the mean age of the patients receiving olmesartan was 57.02±13.86 years. Of the patients receiving captopril, 19 (57.5%) were male, 21 (52.5%) were female, 17 (42.5%) of the patients receiving olmesartan were male and 23 (57.5%) were female. In this study, patients treated with captopril and olmesartan were monitored for 3 hours and the differences between them in pulse and blood pressure measurements were evaluated. When the systolic blood pressures were compared, the difference at the tenth minute was significant, but the difference between the other minutes was not significant. Differences in diastolic blood pressure and heart rate were not significant. Conclusion: Oral administration of olmesartan in emergency hypertensive patients may be an alternative to captopril due to its effectiveness in reducing mortality and morbidity.