Exercises: Holistic health

State the three basic pillars of rest and nighttime well-being (duration, sleep schedules and sleep environment), and explain what specific recommendation you would give for each one to an adolescent.

Explain what benefits regular physical activity provides to the musculoskeletal, circulatory and respiratory systems, citing at least one specific benefit for each.

Look at the figure, which shows a student sitting at a study desk with three details of their posture marked with ?. State the postural hygiene rule corresponding to each of the three details, and explain which health problem each rule prevents.

The WHO recommends that adolescents engage in at least $60\ \text{min}$ of moderate-to-vigorous physical activity daily. A student walks $20\ \text{min}$ to middle school and another $20\ \text{min}$ back, and plays basketball for $40\ \text{min}$ during recess. Calculate whether they meet the recommendation, and explain what type of activity (moderate or vigorous) each activity they perform represents.

Many teenagers use their cell phones in bed before going to sleep. Explain how this habit affects sleep — through screen light and mental stimulation — and suggest two alternative routines that encourage falling asleep.

Explain what mental health is, why it is as important as physical health, and what difference there is between feeling sad or stressed occasionally and having a mental health issue that requires professional help.

Marcos sleeps an average of $5.5\ \text{h}$ from Monday to Friday and states: "It doesn't matter that I sleep little during the week, on Saturday and Sunday I sleep $11\ \text{h}$ and make up for the lost hours". However, he notices that on Mondays he struggles to memorise new concepts, performs worse in class, and feels irritable. Biologically refute Marcos's claim: justify why the brain cannot compensate all at once for five days' worth of memory consolidation and emotional regulation processes, and explain how this shift in schedules disrupts his circadian rhythms.

School backpacks should not exceed $10\ \%$ of body weight. Mateo, who weighs $52\ \text{kg}$, carries a loaded backpack weighing $7\ \text{kg}$, and Lucía, who weighs $40\ \text{kg}$, carries a backpack weighing $6\ \text{kg}$. Calculate the percentage that each person's backpack represents, compare who strays further from the recommendation — even if their backpack weighs less — and propose a three-measure plan to reduce the risk of back pain, justifying each measure.

Analyse Elena's daily routine on a school day: classes at secondary school ($8:00$-$14:30$), after-lunch time on her phone ($14:30$-$16:00$), tutoring classes ($16:00$-$18:00$), homework and studying ($18:00$-$21:00$), dinner watching television ($21:00$-$22:00$), and using her phone in bed ($22:00$-$0:30$). Elena sleeps $6.5\ \text{h}$, does not practice any physical activity, and shows chronic fatigue and concentration issues. Identify the three habits that pose the greatest risk to her health, justify their biological impact, and redesign her afternoon/evening schedule ($14:30$-$23:00$) to fit the recommendations for rest, physical activity, and screen use, while maintaining her academic obligations.