scholarly journals Implementing a Circadian Adaptation Schedule after Eastward Flight in Young Male Athletes

2021 ◽  
Vol 11 (21) ◽  
pp. 9962
Author(s):  
Dean J. Miller ◽  
Gregory D. Roach ◽  
Michele Lastella ◽  
Aaron T. Scanlan ◽  
Charli Sargent
Keyword(s):  
Light Exposure ◽  
Core Body Temperature ◽  
Intervention Group ◽  
Young Male ◽  
Control Group ◽  
Jet Lag ◽  
Time Zone ◽  
Male Athletes ◽  
Main Effects ◽  
Core Body

This study examined the effectiveness of a circadian adaptation schedule in male cricketers after an 8.5 h eastward time zone change. Ten participants (aged 18.7 ± 0.9 y) were randomly assigned to a control group or an intervention group. Participants in the intervention group followed a light exposure schedule in which they were instructed to seek light in the three hours preceding, and avoid light in the three hours following their estimated core body temperature minimum. The rate of adaptation was assessed using the nightly excretion rate of urinary 6-sulphatoxymelatonin (aMT6s). General linear mixed models were conducted to assess the effect of condition (i.e., control and light intervention) on nocturnal secretion of aMT6s. Significant main effects of day (F(7, 35) = 10.4, p < 0.001) were reflected by an increase in nocturnal melatonin excretion (i.e., all participants gradually adapted to the destination time zone). Subjective jet lag decreased by day (F(7, 54) = 22.9, p < 0.001), bedtime was delayed by day (F(7, 54) = 3.1, p = 0.007) and get up time was earlier by day (F(7, 35) = 5.4, p < 0.001). On average, it took 7 days for all participants to return to baseline levels following transmeridian travel. Similarly, it took 7 days for subjective jet lag to alleviate. In the initial 4 days of the protocol, the intervention group registered higher levels of nocturnal urinary melatonin, however, there was no significant differences in the rate of adaptation between the groups. It is possible that participants did not adhere to the intervention or that they followed the intervention but it was ineffective.

Nonphotic entrainment of the human circadian pacemaker

1998 ◽  
Vol 274 (4) ◽  
pp. R991-R996 ◽  
Author(s):  
Elizabeth B. Klerman ◽  
David W. Rimmer ◽  
Derk-Jan Dijk ◽  
Richard E. Kronauer ◽  
Joseph F. Rizzo ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Light Exposure ◽  
Core Body Temperature ◽  
Biological Clock ◽  
Bright Light ◽  
Circadian Pacemaker ◽  
Temperature Rhythms ◽  
Blind Individuals ◽  
Nonphotic Entrainment ◽  
Core Body

In organisms as diverse as single-celled algae and humans, light is the primary stimulus mediating entrainment of the circadian biological clock. Reports that some totally blind individuals appear entrained to the 24-h day have suggested that nonphotic stimuli may also be effective circadian synchronizers in humans, although the nonphotic stimuli are probably comparatively weak synchronizers, because the circadian rhythms of many totally blind individuals “free run” even when they maintain a 24-h activity-rest schedule. To investigate entrainment by nonphotic synchronizers, we studied the endogenous circadian melatonin and core body temperature rhythms of 15 totally blind subjects who lacked conscious light perception and exhibited no suppression of plasma melatonin in response to ocular bright-light exposure. Nine of these fifteen blind individuals were able to maintain synchronization to the 24-h day, albeit often at an atypical phase angle of entrainment. Nonphotic stimuli also synchronized the endogenous circadian rhythms of a totally blind individual to a non-24-h schedule while living in constant near darkness. We conclude that nonphotic stimuli can entrain the human circadian pacemaker in some individuals lacking ocular circadian photoreception.

scholarly journals Effects of Pre-cooling and Per-cooling on Neural, Physiological, and Functional Responses in Active Young Girls

2020 ◽  
Vol 18 (3) ◽  
Author(s):  
Seyedeh Somayeh Razavi ◽  
Amirabbas Monazzami ◽  
Zahra Nikosefat
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Body Temperature ◽  
Repeated Measures ◽  
Blood Pressure Monitoring ◽  
Core Body Temperature ◽  
Control Group ◽  
Functional Responses ◽  
Young Girls ◽  
Core Body

Background: Stressful environments, especially air temperature, have significant effects on human physiological responses to physical activity. Objectives: The current study aimed to determine the effects of pre-cooling and per-cooling on neural, physiological, and functional responses in active young girls. Methods: Twelve active girls (age 24.6 ± 1.4, weight 55.46 ± 8.18, height 165.1 ± 5.91) were tested in three separate sessions with intervals of three days between each session. All subjects performed the Balke test in three groups either without an ice vest (control and pre-cooling) or with an ice vest (per-cooling) in each session, randomly. Pre-cooling was applied with an ice vest for 30 min just before the test, while per-cooling was used with an ice vest from the beginning of the test to exhaustion. A Buerer FT-70 digital thermometer, polar-FT60 heart rate monitoring, Microlife blood pressure monitoring, and ELISA technique were used to measure core body temperature, heart rate, blood pressure, dopamine, cortisol, and lactate dehydrogenase, respectively. Two-way repeated-measures ANOVA was applied to analyze the data with a confidence interval of 95%. Results: The heart rate and core body temperature significantly decreased at the end of the test in the pre-cooling and per-cooling groups (P < 0.05). There was an improved performance with an increase in Tmax in the per-cooling group compared to the control group (P < 0.05) although this difference was not significant in the pre-cooling group compared to the control group (P > 0.05). Dopamine, cortisol, and lactate dehydrogenize increased in the groups in comparison with the pretest (P < 0.05) even though these differences were not significant in the comparison between the groups (P > 0.05). Conclusion: The findings suggest that pre-cooling and per-cooling could be used as a beneficial method to improve performance due to not only a decrease in core body temperature and heart rate but also an increase in the level of dopamine and cortisol. Moreover, per-cooling was more effective than pre-cooling to increase performance.

scholarly journals Clinical picture and treatment of jet lag

2011 ◽  
Vol 152 (50) ◽  
pp. 2021-2024
Author(s):  
Péter Igaz ◽  
Zsolt Tulassay
Keyword(s):  
Clinical Picture ◽  
Sleep Disturbances ◽  
Light Exposure ◽  
Somatic Symptoms ◽  
Sleep Time ◽  
Health Problems ◽  
Jet Lag ◽  
Time Zone ◽  
Major Health ◽  
Light Darkness

Symptoms associated with rapid time zone crosses represent one of the major health problems associated with commercial flights. This condition is termed jet lag that is characterized by sleep disturbances (insomnia, sleepiness), somatic symptoms, and decrease in mental and physical outputs. Difference between the light-darkness cycles of the destination and internal homeostatic rhythm is responsible for the syndrome. Restitution of the internal rhythm by appropriate light exposure or melatonin, optimal sleep time and duration, and drugs can be used in its treatment. Orv. Hetil., 2011, 152, 2021–2024.

Role of the hypothalamic PVN in the reflex reduction in mesenteric blood flow elicited by hyperthermia

2008 ◽  
Vol 295 (6) ◽  
pp. R1874-R1881 ◽  
Author(s):  
Feng Chen ◽  
Melissa Dworak ◽  
Yuliang Wang ◽  
Joo Lee Cham ◽  
Emilio Badoer
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Blood Flow ◽  
Body Temperature ◽  
Core Body Temperature ◽  
Separate Group ◽  
Control Group ◽  
Mesenteric Blood Flow ◽  
Significant Difference ◽  
Core Body

The hypothalamic paraventricular nucleus (PVN) is an important integrative center in the brain. In the present study, we investigated whether the PVN is a key region in the mesenteric vasoconstriction that normally accompanies an increase in core body temperature. Anesthetized rats were monitored for blood pressure, heart rate, mesenteric blood flow, and vascular conductance. In control rats, elevation of core body temperature to 41°C had no significant effect on blood pressure, increased heart rate, and reduced mesenteric blood flow by 21%. In a separate group of rats, muscimol was microinjected bilaterally (1 nmol/side) into the PVN. Compared with the control group, there was no significant difference in the blood pressure and heart rate responses elicited by the increase in core body temperature. In contrast to control animals, however, mesenteric blood flow did not fall in the muscimol-treated rats in response to the elevation in core body temperature. In a separate group, in which muscimol was microinjected into regions outside the PVN, elevating core body temperature elicited the normal reduction in mesenteric blood flow. The results suggest that the PVN may play a key role in the reflex decrease in mesenteric blood flow elicited by hyperthermia.

scholarly journals Cooling Interventions Among Agricultural Workers: A Pilot Study

2020 ◽  
pp. 216507992097652
Author(s):  
Roxana Chicas ◽  
Nezahualcoyotl Xiuhtecutli ◽  
Lisa Elon ◽  
Madeleine K. Scammell ◽  
Kyle Steenland ◽  
...  
Keyword(s):  
Body Temperature ◽  
Core Body Temperature ◽  
Heat Exposure ◽  
The United States ◽  
Agricultural Workers ◽  
Control Group ◽  
Temperature Threshold ◽  
Convenience Sample ◽  
Ambient Temperatures ◽  
Core Body

Background Adverse health effects among agricultural workers due to chronic heat exposure have been characterized in the literature as not only due to high ambient temperatures but also due to intensive manual labor in hot and humid conditions. The aim of this study was to use biomonitoring equipment to examine the effectiveness of selected cooling devices at preventing agricultural workers from exceeding the core body temperature threshold of 38.0°C (Tc38) and attenuating heat-related illness symptoms. Methods A convenience sample of 84 agricultural workers in Florida was randomized to one of four groups: (a) no intervention, clothing as usual; (b) cooling bandana; (c) cooling vest; and (d) both the cooling bandana and cooling vest. Biomonitoring equipment worn by the participants included core body temperature monitor and an accelerometer to capture physical activity. Findings A total of 78 agricultural workers completed one intervention workday trial. Compared with the control group, the bandana group had lower odds of exceeding Tc38 (odds ratio [OR] = 0.7, 90% confidence interval [CI] = [0.2, 3.2]) and the vest group had higher odds of exceeding Tc38 (OR = 1.8, 90% CI = [0.4, 7.9]). The simultaneous use of cooling vest and bandana showed an effect little different from the control group (OR = 1.3, 90% CI = [0.3, 5.6]). Conclusion/Application to Practice This is the first field-based study to examine cooling intervention among agricultural workers in the United States using biomonitoring equipment. This study found that using a bandana while working in a hot agricultural environment has the potential to be protective against exceeding the recommended Tc38 threshold.

scholarly journals Organic selenium effect on body temperature and body weight in broilers

2017 ◽  
Vol 1 (4) ◽  
pp. 332-336
Author(s):  
Adrian Răduță ◽  
Dumitru Curcă
Keyword(s):  
Body Weight ◽  
Body Temperature ◽  
Core Body Temperature ◽  
Control Group ◽  
Feed Conversion ◽  
Organic Selenium ◽  
Average Temperature ◽  
Cholesterol Levels ◽  
Core Body ◽  
Experimental Group

Abstract The research was conducted on a group of 20 3-weeks-old chicken from the Cobb breed that were divided into two batches. Both batches received a 21/1 ratio feed diet for broiler chicken in their finishing period. The experimental group feed was supplemented with 0.5 ppm selenium, with 0.25 ALKOSEL R397 g/kg mixed fodder. 30 days into this feeding regime, the following determinations were made weekly: body weight, body temperature and computerized thermography of the comb and wattle. The obtained results were tabled and bio statistically analyzed revealing that individuals in the experimental batch showed statistically significant increases of the values for body weight (average body weight was 14.78% larger than that of the control batch) and of the temperature measured in the combs (average temperature was 12.97% higher) and wattles (average temperature was 4.12% higher). The experimental group also registered a higher core body temperature, but not statistically significant in comparison with the control group. Association of the higher values of core and peripheral body temperature with increased body weight in the individuals from the experimental group, correlated with an increased number of red blood cells and lower cholesterol levels suggest an improved basal metabolism and a better feed conversion.

scholarly journals Therapeutic Effects of Tai Chi in Patients with Parkinson’s Disease

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Hye-Jung Choi ◽  
Carol Ewing Garber ◽  
Tae-Won Jun ◽  
Young-Soo Jin ◽  
Sun-Ju Chung ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Physical Function ◽  
Significant Interaction ◽  
Tai Chi ◽  
Intervention Group ◽  
Control Group ◽  
Therapeutic Effects ◽  
Positive Effects ◽  
Main Effects

Objective. The purpose of the study was to investigate the effects of a 12-week program of therapeutic Tai Chi on the motor function and physical function of idiopathic Parkinson’s disease patients (PDs). Methods. The participants were 22 clinically stable PDs in Hoehn-Yahr stages 1-2 randomly assigned to a therapeutic Tai Chi group (TTC, N=11) or a control group (CON, N=9). Two subjects in control group did not complete the study for personal reasons. TTC was performed three days a week (60 min/session). Motor symptoms by the UPDRS were assessed, and tests of physical function were administered before and after the 12-week trial. Results. The TTC group, as compared to the CON group, showed changes in the mentation, behavior, mood, and motor scales of the UPDRS (P<0.05, P<0.01, resp.), with no significant main effects on the activities of daily living scale (ADL). However, there was a significant interaction between the time and intervention group on ADL (P<0.05). There were no significant main effects for any of the physical function variables. There were significant interaction effects in balance and agility (P<0.05, resp.). Conclusions. This study showed that TTC training had modest positive effects on the functional status of Parkinson’s disease patients.

scholarly journals Improving Wellness of Operating Room Personnel: A Light-Based Intervention on Perceived Nursing-Related Stress

2021 ◽  
Vol 12 ◽  
Author(s):  
Gilles Guerrier ◽  
Dimitri Margetis ◽  
Christine Agostini ◽  
Zakia Machroub ◽  
Sophie Di Maria
Keyword(s):  
Health Care ◽  
Operating Room ◽  
Light Exposure ◽  
Intervention Group ◽  
Well Being ◽  
Controlled Study ◽  
Control Group ◽  
Crossover Fashion ◽  
Score Difference ◽  
Related Stress

Background: Nursing is an emotionally demanding and physically draining occupation. Well-being of health care workers is essential to achieve success in care and have good cooperation relationships with other health professionals.Objective: The purpose of this study was to evaluate the effectiveness of a light-based intervention on perceived nursing-related stress in health care personnel working in an operating room environment.Methods: A total of 84 nurses participated in this randomized, cross-over controlled study. Intervention consisted of 4 weeks of bright blue-enriched light exposure using a LED head-mounted portable device (n = 42) or no light exposure (n = 42) separated by a 2-week washout period in a crossover fashion. Participants completes questionnaires for the Nursing Stress Scale (NSS).Results: Intervention and control groups were comparable in terms of demographics, with a median age of 34 (IQR: 27–49) and 69 (82%) female. The mean baseline NSS score was similar in both groups before intervention. The NSS score of the intervention group was significantly lower after intervention than the baseline score: the NSS score difference before and after intervention was 15.1 (SD 7.6) (p &lt; 0.001) and 19.7 (SD 7.5) (p &lt; 0.001) during the two successive periods of intervention, respectively. The cross-group comparison after intervention showed a significantly higher NSS score difference after intervention in the intervention group than the control group: 15.1 (SD 7.6) vs. 1.4 (SD 8.4) (p &lt; 0.001) and 19.7 (SD 7.5) vs. 1.7 (SD 8.9) (p &lt; 0.001) during the two successive periods of intervention, respectively.Conclusion: Alternative person-directed initiatives should be considered to improve the well-being of the health workforce in operating rooms, especially during the coronavirus pandemic.

scholarly journals Reducing Subjective Fatigue among University Teachers of Indonesia

2014 ◽  
Vol 1 (1) ◽  
pp. 22-28
Author(s):  
Gurdani Yogisutanti ◽  
Hari Kusnanto ◽  
Lientje Setyawati ◽  
Yasumasa Otsuka
Keyword(s):  
Training Program ◽  
Occupational Safety ◽  
Intervention Group ◽  
Health And Safety ◽  
Work Place ◽  
Control Group ◽  
University Teachers ◽  
Subjective Fatigue ◽  
Quasi Experimental ◽  
Main Effects

Objectives: This study aimed to reduce subjective fatigue and increase knowledge of fatigue among university teachers.Methods: A quasi experimental design was used to examine the efficacy of fatigue-controlled training among university teachers in intervention and control groups. As many as 37 teachers from intervention group and 40 teachers from control group completed T1 (baseline) and T2 (follow-up) data on knowledge, subjective fatigue using an item subscale of Self-Diagnosis Checklist for Assessment of Workers’ Accumulative Fatigue.Results: The results of repeated measured analysis of variances showed that training program for fatigue was associated with higher knowledge and lowered subjective fatigue compared with control group. Significant main effects of fatigue training on knowledge, and subjective were revealed. After controlling for all covariates, the repeated measured analysis of variances showed significant main effects of fatigue training program on knowledge and subjective fatigue.Conclusions: Fatigue-controlled training program reported in this study was efficacious to enhance university teachers’ knowledge of fatigue and occupational health and safety at a work place. University teachers experienced lower subjective fatigue after been trained. This program may be considered as an initial strategy for occupational safety and health program in education setting to reduce fatigue particularly among university teachers. The training should be conducted frequently to enable university teachers controlled their fatigue.DOI: http://dx.doi.org/10.3126/ijssm.v1i1.9327 Int. J. Soc. Sci. Manage. Vol.1(1) 2014 22-28  

The effect on the anaesthetised rabbit of warming the breathing circuit with 40°C liquid

2020 ◽  
Vol 25 (9) ◽  
pp. 1-5
Author(s):  
Anna Linda Nógrádi ◽  
Márton Battay ◽  
Iain Cope ◽  
Tibor Németh
Keyword(s):  
Body Temperature ◽  
Breathing Circuit ◽  
Core Body Temperature ◽  
The Body ◽  
Control Group ◽  
Gas Mixture ◽  
Water Chamber ◽  
Ambient Room Temperature ◽  
Inhalational Anaesthesia ◽  
Core Body

During every surgical procedure, one of the aims is to reduce the risk of anaesthesia. Some factors can be influenced, such as core body temperature. The authors wanted to investigate a method that was cheap, efficient and also easy to use in everyday veterinary practice, as well as in more remote settings. The study examined the temperatures of 30 rabbits during inhalational anaesthesia, when using a facemask and T-piece circuit. The rabbits were put in three groups, with two groups inhaling the warmed gas mixture. The inhalational breathing circuit in these two groups was immersed in a 40 ± 1°C heated water chamber. The circuit was 60 cm in the first group and 80 cm in the second group. The third control group inhaled a gas mixture at ambient room temperature. The results indicated that the longer the piece of circuit that was warmed, the less the body temperature of the rabbit dropped. In the control group, at the 40th minute of anaesthesia, the average drop in body temperature was −1.28°C, while in the 60 cm heated group it was −0.65°C, and in the 80 cm heated group it was −0.27°C.

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