Static and Dynamic Balance Indices among Kindergarten Children: A Short-Term Intervention Program during COVID-19 Lockdowns.

The COVID-19 pandemic outbreak had a negative impact on kindergarten activities. These young children, who had been compelled to stay home during lockdowns, suffered a lack of movement and loss of mobility, resulting in deteriorated physical motor skills. Lack of sufficient motor experience in early childhood can impair children's motor and cognitive development. Balance skills are fundamental to all other motor abilities, from the most basic movements to the most complex motor skills. The purpose of this study was to implement a short-term physical activity program, which may have a direct effect on children's fundamental balance ability. Ninety-six kindergarten children (45 boys and 51 girls), aged 4-6 years, participated in the study. Data were analyzed using three-way ANOVA and interaction analyses. The results suggest that short, focused, and dedicated balance training programs have a beneficial influence on the static balance of preschoolers and can mitigate some of the negative physical outcomes of lockdowns. In conclusion, this study indicates that a short-term physical training program had a positive effect on the motor abilities of preschoolers after COVID-19-related lockdowns. More research is needed in order to fully understand the complete impact of the worldwide health crisis and the best ways in which to address it.

Physiological Differences Between Heat Tolerant and Heat Intolerant Young Healthy Women.

Purpose: Heat intolerance (HI) is determined in the Israel Defense Force according to a heat tolerance test (HTT) before returning to duty after an exertional heat stroke (EHS) event. Recently, increased numbers of female combatants resulted in an increased number of EHS cases among women and a higher percentage of heat intolerance (HI) individuals. We aimed to evaluate the differences between tolerance to heat among women performing an HTT in relation to their menstrual cycle phase. Method: Thirty-three female participants were sorted into two groups: HI and heat tolerant (HT) according to two HTTs performed during both the luteal and follicular phases of the menstrual cycle or while consuming and during a break from consuming contraceptives. Results: HT women had an 18% higher maximal oxygen uptake (p < .005, 95% CI [2.6,9.8]) and 1.2% lower skin temperature in the HTT at the during and follicular phases (p < .01, 95% CI [0.12,0.77]) and 1.7% lower at the off and luteal phases (p < .001, 95% CI [0.34,0.92]). The mean sweat rate was 14% lower among the HI group only at the HTT at the during and follicular phases (p < .05, 95% CI (3,88)]). Conclusion: We found that HT can be predicted using aerobic capacity and core body temperature. Moreover, during the luteal phase, women presented altered thermoregulation that decreased the probability of being HT. This emphasizes the importance of considering the HT/HI criteria in the HTT for women, according to their aerobic ability and menstrual-cycle phase.

Probability of Heat Intolerance: Standardized Interpretation of Heat-Tolerance Testing Results Versus Specialist Judgment.

CONTEXT: The heat-tolerance test (HTT) is a screening tool for secondary prevention of exertional heat illness by the Israel Defense Forces. To discern participant tolerance, recruits are exposed to intermediate environmental and exercise stresses, and their physiological responses, core temperature, and heart rate are monitored. When their physiological measures rise at a higher rate or exceed the upper levels of absolute values compared with other participants, heat intolerance (HI) is diagnosed. OBJECTIVE: To develop a mathematical model to interpret HTT results and provide a quantitative estimate of the probability of heat tolerance (PHT). DESIGN: Cross-sectional study. SETTING: Warrior Health Research Institute. PATIENTS OR OTHER PARTICIPANTS: The HTT results of 175 random individuals tested after an episode of exertional heat illness were classified qualitatively and then divided into training (n = 112) and testing (n = 63) datasets. All individuals were male soldiers (age range = 18-22 years) who had sustained an episode of definitive or suspected exertional heat stroke. MAIN OUTCOME MEASURE(S): Based on the decision algorithm used by the Israel Defense Forces for manual interpretation of the HTT, we designed a logistic regression model to predict the heat-tolerance state. The model used a time series of physiological measures (core temperature and heart rate) of individuals to predict the manually assigned diagnosis of HT or HI. It was initially fitted and then tested on 2 separate, random datasets. The model produced a single value, the PHT, and its predictive ability was demonstrated by prediction-density plots, receiver operating characteristic curve, contingency tables, and conventional screening test evaluation measures. RESULTS: According to prediction-density plots of the testing set, all HT patients had a PHT of 0.7 to 1. The receiver operating characteristic curve plot showed that PHT was an excellent predictor of the manual HT interpretations (area under the curve = 0.973). Using a cutoff probability of 0.5 for the diagnosis of HI, we found that PHT had sensitivity, specificity, and accuracy of 100%, 90%, and 92.06%, respectively. CONCLUSIONS: The PHT has the potential to be substituted for manual interpretation of the HTT and to serve in a variety of clinical and research applications.

Effects of basic combat training on iron status in male and female soldiers: a comparative study.

OBJECTIVE: Iron is an essential micronutrient known to affect physical and cognitive performance. Studies indicate a significant reduction in iron status in female Soldiers immediately following military training, although the comparative effects of military training on iron status between male and female Soldiers have not been examined. The objective of this study was to compare the longitudinal effects of US Army basic combat training (BCT) on iron status indicators in a group of male and female Soldiers. METHODS: A total of 154 male and female Soldiers (89 and 65, respectively) completed the study. Blood was collected at 4 time-points during BCT (weeks 0, 3, 6, 9) and dietary iron intake was assessed at weeks 0 and 9. Iron status indicators included hemoglobin, serum ferritin (SF), soluble transferrin receptor (sTfR), and transferrin saturation (TS). RESULTS: Iron status was greater in male Soldiers than female Soldiers, as hemoglobin and SF levels were higher (P<.05) and sTfR levels were lower (P<.05) in males as compared to females at each time-point. Despite a mean increase of greater than 25% in iron intake (mg/day) among both male (15±13 to 20.2±14.4) and female Soldiers (12.8±9.7 to 16±6.2) over the course of BCT, iron status declined in both groups. As compared to baseline, SF declined (P<.05) by 21% and 47%, sTfR increased (P<.05) by 17% and 30%, and TS declined (P<.05) by 23% and 54% in male and female Soldiers, respectively, over the course of BCT. CONCLUSIONS: These data indicate that although dietary iron intake improves, iron status declines in both male and female Soldiers during BCT, and the decline in female Soldiers is of a greater magnitude. Future studies should aim to determine the mechanism by which iron status declines during military training, with a focus on functional outcomes affecting Soldier health and performance.