DISCUSSION
Based on BMI, more than half of the enrolled athletes (59.5%) gained weight during the lockdown from March to July 2020. Weight, height, BMI, weight percentile, and weight-for-height Z score increased significantly during that period. Weight gain among athletes can greatly affect their performance. For many athletes across various sport disciplines there is a direct causal connection between success and low body weight [10] .
Contrary to the coach instructions, almost two thirds of the enrolled athletes didn’t perform any home exercises. With further analysis significantly more of those athletes who were not complaint to the home exercise program gained weight during the pandemic lockdown. This result comes in agreement with Zeigler and associates [11] who reported lack of exercise as a risk factor for weight gain during the COVID pandemic self-quarantine periods.
Lack of exercise and its related overweight problems can gravely impact the immune system of those athletes. It has been mentioned that although moderate-levels of exercise can boost overall immunity [12], intensive and prolonged physical exertion has been linked with an ‘open-window’ of impaired immunity up to 72 hours after the exercise [13] . Nevertheless, Campbell and Turner, [14] challenged the latter theory and reinforced that it is a misconception to label any form of acute exercise as immunosuppressive, and, instead, they stated that exercise most likely improves immune competency across the lifespan. Another hit to the immune system can come from the extra weight. In addition to metabolic and cardiovascular obesity-related diseases, recent evidence suggested that obesity might affect immune system function [15] .  From another perspective obesity was linked to severity of COVID 19 infection among children in Canada [16] and USA [17] . It is thus clear that exercise is essential for boosting the immune system which is greatly needed during pandemics not to mention the benefits of weight control in this domain.
The mean sleep hours per day during the lockdown were 11.1 which is within the appropriate sleeping hours of this age group as stated by the American Academy of Sleep Medicine [18] . Although sleeping hours were significantly higher among athletes who gained weight and all of them had CHQS above 41, which reflected their disturbed sleep pattern; the higher CHQS among the athletes who gained weight didn’t reach statistical significance. The previous findings are supported by the report of Jarrin and associates [19] regarding the relation between disturbed sleep and weight gain.
All participants reported screen time ranging between 4-10 hours/day and played video games with an average time of 3.2 hours daily. Although both screen time and its important element, which is video gaming, were found increased among athletes who gained weight, these results didn’t reach statistical significance. Goncalves and collaborators, [20] reported that screen time is related to obesity among children yet video gaming role is still inconclusive with a promising role of exergame play as a tool for weight reduction [21] .
Only 10 (27%) of our enrolled athletes had tics during the lockdown, 5 (13.5%) reported feeling unhealthy during the lockdown, and 9 (24.3%) lost a family member during this particular period. Although these points represent psychosocial stress and are among the non-chemical stressors affecting childhood obesity [22] , this wasn’t the case among our studied young athletes.
Although the participants’ mothers had a relatively high depression score it correlated negatively with the increased BMI of the athletes. On the other hand, the high anxiety score of mothers correlated positively with the athletes increase in BMI. Although Marshall and associates [23] reported that maternal depression influences children’s weight and may increase risk of obesity, Vehmeijer and associates [24] confirmed the current study findings and reported that maternal anxiety was associated with higher children BMI with no associations observed for maternal depression.
The athletes mean QoL Score filled in March 2020 worsened significantly compared to that of July 2020. The previous finding can be easily interpreted in view of a latest publication by Ghosh and collaborators, [25] . The latter authors reported that being quarantined in homes and institutions may impose greater psychological burden on children than the physical sufferings caused by the virus. School closure, lack of outdoor activity, aberrant dietary and sleeping habits are likely to disrupt children’s usual lifestyle and can potentially promote monotony, distress, impatience, annoyance and varied neuropsychiatric manifestations. Additionally, in the current study a significant negative correlation was found between the increase in BMI and the change of QoL from March to July 2020. QoL worsening with the increase in BMI is due to the fact that children and adolescents with obesity frequently report an impaired health-related quality of life [26] , which can be defined as ‘the impact of health or disease on physical, mental, and social well-being from the patient’s point of view’ [27] .
In conclusion, the recent COVID 19 pandemic lockdown had both physical and psychological effects on Egyptian young athletes with plausible interrelations correlating them. Additionally, maternal psychological status during these extreme measures has their reflections on the children. Since athletes‘ performance is vulnerable to such effects, they should be aware of the need for weight control when outdoors physical activity is necessarily restricted by pandemic control and preventive measures. Compliance to home exercising schedules with less screen time and video gaming can be of crucial importance to them during these extenuating circumstances. It is prudent to say that following all these previous measures can have a positive effect on the athletes QoL.