The effect of background audio and audiovisual stimuli on students' autonomic responses during and after an experimental academic examination.

BACKGROUND: Due to the Covid-19 pandemic lockdown during the online-distant education period, certain students tended to combine their courses and homework with TV or social media news or other media content, such as classical music, including a wealth of audio and audiovisual stimuli. As the audio and audiovisual stimuli existing in a learning environment may affect students' autonomic nervous system (ANS) responses negatively, the present study aimed to monitor the impact of background TV, classical music, and silence on students' ANS activity represented by heart rate (HR), heart rate variability (HRV), blood volume amplitude (BVA), and skin conductance level (SCL) during and after an experimental academic examination. METHOD: Seventy-six students were randomly allocated to background TV, classical music, or silence groups. The experiment with repeated measures design consisted of four consecutive periods: baseline, anticipation, challenge, and recovery, lasting 4 min each. RESULTS: Within-subject analyses indicated significant HRV decrement only in the background TV group. Regardless of the experimental groups, HR and SCL increased while BVA decreased during the task. In addition, the between-subject analysis showed that the background TV group experienced significantly larger changes in HR and HRV parameters compared to the other experimental groups relative to their respective baseline measurements. CONCLUSIONS: Based on these results, we concluded that relative to classical music and silence, background TV, including audiovisual and verbal stimuli, extant in a learning environment might raise students' sympathetic activity. Further, classical music, without lyrics, may suppress the withdrawal of vagal activity and elevate the autonomic regulation capacity during the academic reading comprehension task. HRV is a more valid and reliable indicator of students' autonomic responses during a challenging academic task.

The Short-Term Effect of Occupational Levels of 50 Hz Electromagnetic Field on Human Heart Rate Variability.

Previous studies have indicated that there is no consensus on the effects of extremely low-frequency electromagnetic (ELF-EMF) exposure on the cardiovascular system. This study aimed to explore the short-term effect of ELF-EMF exposure on heart rate (HR) and HR variability (HRV). The sample consisted of 34 healthy males aged 18-27 years. The participants were randomly assigned to the EMF (n = 17) or the Sham group (n = 17). We employed a double-blind repeated-measures design consisting of three 5 min experimental periods. The chest region of each individual in the EMF group was exposed to 50 Hz, 28 µT, linear polarized, continuous EMF during the EMF exposure period. HR and HRV data were recorded continuously by using a photoplethysmography sensor. Within-subject statistical analysis indicated a significant HR deceleration in both the EMF and Sham groups. However, the standard deviation of the NN intervals (SDNN), root mean square of successive differences (RMSSD), low-frequency (LF), and high-frequency (HF) powers increased only in the EMF group and remained stable in the Sham group. We also compared the same HRV indices measured during the EMF and Sham periods between the two experimental groups. The between-subject analysis results demonstrated significantly higher SDNN, RMSSD, LF, and HF values in the EMF group than in the Sham group. The LF/HF ratio did not change significantly within and between groups. On the basis of these results, we concluded that short-term exposure of the chest region to ELF-EMF could potentially enhance parasympathetic predominance during the resting condition. Bioelectromagnetics. 2021;42:60-75. © 2020 Bioelectromagnetics Society.

Effect of Force Sense to Active Joint Position Sense and Relationships between Active Joint Position Sense, Force Sense, Jumping and Muscle Strength.

We aimed to investigate the effect of external load on the joint position sense (JPS) accuracy and its relation to the target jump height. The present study also aimed to explore the relationship between force sense (FS) and maximum voluntary isometric contraction (MVIC). Participants' MVIC levels were determined during the 45-degree knee extension task. Then, participants were asked to execute a knee JPS task with external load (EL-JPS) and with no-load (EL-JPS). To assess jumping accuracy participants were instructed to jump with their 50% of maximum jump height. Results indicated that EL-JPS error values were lower than NL-JPS. EL-JPS was correlated to jumping errors. However, the relationship between NL-JPS and jumping errors was not significant. A significant correlation was found between MVIC and FS errors.

Autonomic Cardiac Activity Among Novice Archers During Baseline, Shooting, and Recovery.

Tok, S, Dal, N, Zekioglu, A, Çatikkas, F, Balikçi, I, and Dogan, E. Autonomic cardiac activity among novice archers during baseline, shooting and recovery. J Strength Cond Res 34(9): 2627-2635, 2020-In the present study, we aimed to investigate whether heart rate variability (HRV) of novice archers may vary during baseline, shooting, and recovery periods. In addition, we aimed to explore whether HRV may have different patterns between successful and less successful archers and man and woman archers. The sample consisted of 39 (12 woman) novice archers ranging in age from 21 to 27. Baseline HRV activity was measured in the first stage of the experiment. Then, participants shot 10 arrows, from 18 m to an 80 cm diameter target, whereas their HRV was measured. Lastly, HRV recovery response was measured immediately after shooting. HRV was represented as low frequency (LF), high frequency (HF), and LF/HF ratio. When considering the entire sample, repeated measures of analysis of variance (ANOVA) indicated that only HF power differed among baseline, shooting, and recovery periods [F(2, 76) = 6.90, p = 0.002, ω = 0.15]. When the data partitioned, based on the median split of the shooting scores, repeated measures of ANOVA demonstrated that none of the HRV components differed in the less successful group from baseline to recovery. However, in the successful group, both LF [F(1.47, 30.98) = 4.75, p = 0.024, ω = 0.18] and HF [F(1.54, 32.37) = 6.61, p = 0.007, ω = 0.24] power significantly differed among baseline, shooting, and recovery. No differences were found between man and woman archers in terms of HRV indices. The results of the present study indicated that physical activities requiring the use of perceptual motor skills, in addition to physical qualities, may lead to different HRV responses. Moreover, coaches aiming to develop archers' shooting accuracy may take into account LF power measured during an arrow shooting session.

The Effects of Red Versus Blue Lights and Neuroticism on Voluntary Biceps Brachii Muscle Contraction.

This study investigated the effects of red and blue monochromatic lights and neuroticism on athletes' maximal isometric voluntary contraction (iMVC) level of the biceps brachii muscle. During elbow flexion, we measured iMVCs under a white light (control) condition and under red and blue light conditions. Under red light (vs. white and blue), participants demonstrated a greater iMVC level. Further, based on a median split of the athletes' scores on Tatar's Five Factor Personality Inventory, high and low neuroticism groups showed no red light differences, while, in the blue light condition, participants high in neuroticism increased the iMVC level by 4.04% and those low in neuroticism decreased iMVC level by 6.31%. Thus, the effect of colored light on athletes' motor output varied with individual personality differences in neuroticism.

The relationship of anthropometric measurements with psychological criteria in female athletes.

Sports and exercise settings as well as other socio-cultural environments emphasize a thin and physically fit female body. However, there is a clear need for a better understanding of the physical and psychological correlates of social physique anxiety and body image dissatisfaction in female athletes. This study aimed to examine the association of the social physique anxiety, body image satisfaction, and personality with the anthropometric measurements in female college athletes according to their sport type using the Co-Plot technique. The sample included 63 female athletes ranging in age from 18 to 26. Results of the Co-Plot analysis revealed a significant association among social physique anxiety, personality and anthropometric measurements. This means that certain physical measurements may lead to greater social physique anxiety and body image dissatisfaction in female athletes. It was found that females having higher levels of social physique anxiety and thus, lower levels of body image satisfaction may be less emotionally stable and more negatively perfectionist. In conclusion, the results of the present study provided evidence to the claim that both physical self-perception and anthropometric measurements may be closely associated with psychological criteria in female athletes.

The Effects of Positive and Negative Feedback on Maximal Voluntary Contraction Level of the Biceps Brachii Muscle: Moderating Roles of Gender and Conscientiousness.

We investigated the effect of positive and negative feedback on maximal voluntary contraction (MVC) of the biceps brachii muscle and explored the mediating effects of gender and conscientiousness. During elbow flexion, MVCs were measured in positive, negative, and no-feedback conditions. Participants were divided into high- and low-conscientiousness groups based on the median split of their scores on Tatar's five-factor personality inventory. Considering all participants 46 college student athletes (21 female, 28 male), positive feedback led to a greater MVC percentage change (-5.76%) than did negative feedback (2.2%). MVC percentage change in the positive feedback condition differed significantly by gender, but the negative feedback condition did not. Thus, positive feedback increased female athletes' MVC level by 3.49%, but decreased male athletes' MVC level by 15.6%. For conscientiousness, MVC percentage change in the positive feedback condition did not differ according to high and low conscientiousness. However, conscientiousness interacted with gender in the positive feedback condition, increasing MVC in high-conscientiousness female athletes and decreasing MVC in low-conscientiousness female athletes. Positive feedback decreased MVC in both high- and low-conscientiousness male athletes.

The effects of verbal encouragement and conscientiousness on maximal voluntary contraction of the triceps surae muscle in elite athletes.

We investigated the effect of verbal encouragement on maximal voluntary contraction (MVC) level of the triceps surae muscle group. Our secondary focus was to examine whether the effect of verbal encouragement on MVC level varies as a result of conscientiousness. While the participants performed plantar flexion, MVCs of the triceps surae muscle group were measured using rectified and smoothed surface electromyography (rsEMG) during the absence and presence of verbal encouragement. Participants completed questions from the Five Factor Personality Inventory concerning conscientiousness and were divided into high- and low-conscientiousness groups according to a median split. The sample included 30 female and 53 male elite athletes. In the entire cohort, there was no significant difference in MVCs with and without verbal encouragement. When the sample was partitioned by conscientiousness scores, verbal encouragement led to a significant increase in MVC in the low-conscientiousness group, whereas verbal encouragement led to a non-significant decrease in MVC in the high-conscientiousness group. Percentage change in MVC across experimental conditions was significantly different between the groups, with a 9.72% increase during verbal encouragement of the low-conscientiousness group, and a 2.47% decrease during verbal encouragement of the high-conscientiousness group.

Psychophysiological responses to competition and the big five personality traits.

This study examines the relationship between psychophysiological arousal, cognitive anxiety, and personality traits in young taekwondo athletes. A total of 20 male and 10 female taekwondo athletes (mean age = 18.6 years; ± 1.8) volunteered for the study. The Five Factor Personality Inventory and the state scale of the Spielberger State-Trait Anxiety Inventory (STAI) were used to measure personality and cognitive state anxiety. Electrodermal activity (EDA) was measured twice, one day and approximately one hour prior to the competition, to determine psychophysiological arousal. Descriptive statistics, Pearson product-moment correlations, and stepwise regression were used to analyze the data. Several "Big Five" facets were related to the EDA delta scores that were measured both one day and one hour before the competition. Two stepwise regressions were conducted to examine whether personality traits could significantly predict both EDA delta scores. The final model, containing only neuroticism from the Big Five factors, can significantly explain the variations in the EDA delta scores measured one day before the competition. Agreeableness can significantly explain variations in the EDA delta scores measured one hour before the competition. No relationship was found between cognitive anxiety and the EDA delta scores measured one hour before the competition. In conclusion, personality traits, especially agreeableness and neuroticism, might be useful in understanding arousal responses to competition.