Q.Explain the WHO exercise guidelines for the different age groups — infants and toddlers (below 5 years), children and adolescents (5–17 years), adults (18–64 years) and older adults (65 years and above) — stating the type, duration and frequency of activity recommended for each.

The World Health Organization prescribes distinct physical-activity targets for each stage of life, recognizing that developmental needs and physiological capacities change from infancy to old age.

Infants (under 1 year) should be physically active several times throughout the day in a variety of ways, particularly through interactive floor-based play. For those not yet mobile, at least 30 minutes of tummy time spread across the day is essential to develop motor skills and prevent positional plagiocephaly.

Children and adolescents (5–17 years) require at least 60 minutes of moderate-to-vigorous physical activity every day. The bulk of this should be aerobic — running, cycling, swimming — to build cardiovascular fitness. On at least three days per week, the activity should include vigorous-intensity work and exercises that strengthen muscles and bones, such as jumping, climbing or resistance games.

Adults (18–64 years) should accumulate 150–300 minutes of moderate-intensity aerobic activity per week (brisk walking, recreational cycling) or 75–150 minutes of vigorous-intensity activity (running, fast swimming), or an equivalent combination. In addition, muscle-strengthening activities involving all major muscle groups should be performed on two or more days per week to maintain lean mass and metabolic health. …

Physical inactivity is a leading risk factor for non-communicable diseases worldwide. The World Health Organization has therefore issued evidence-based guidelines tailored to the developmental and physiological needs of each age group. Understanding these recommendations is essential for designing safe, effective activity programs in schools, communities and clinical settings.

Infants and Toddlers (Below 5 Years)

For infants under 1 year, the emphasis is on frequent, varied movement throughout the day rather than structured exercise. Infants should be physically active several times daily in safe, supervised environments. For those not yet mobile, at least 30 minutes of tummy time spread across the day is prescribed. Tummy time strengthens the neck, shoulder and core muscles, supports motor development and prevents positional plagiocephaly (flat-head syndrome). Activities include floor-based play, reaching, grasping and interactive games with caregivers.

Toddlers aged 1–2 years should accumulate at least 180 minutes of varied physical activity spread throughout the day, at any intensity. This includes light activities like standing play, walking and active games. Sedentary screen time is not recommended for children under 2 years, and prolonged restraint (in strollers, high chairs) should be limited to one hour at a time.

Children aged 3–4 years also require at least 180 minutes of physical activity daily, but at least 60 minutes of this should be moderate-to-vigorous intensity. Activities include running, jumping, climbing, dancing and active play. The goal is to build fundamental movement skills, support healthy growth and establish lifelong habits.

Children and Adolescents (5–17 Years)

This age group requires at least 60 minutes of moderate-to-vigorous physical activity every day. The activity should be mostly aerobic, engaging large muscle groups and elevating heart rate — examples include brisk walking, cycling, swimming, running and active games like tag or football.

In addition, vigorous-intensity aerobic activity and activities that strengthen muscle and bone should be incorporated at least 3 days per week. Vigorous activities include running, fast cycling, competitive sports and aerobic dance. Muscle-strengthening activities include climbing, push-ups, resistance exercises and gymnastics. Bone-strengthening activities — those that produce an impact or tension force on bones — include jumping, skipping, basketball and running.

This period is critical for developing cardiorespiratory fitness, muscular strength, bone density and motor skills. Regular activity also supports cognitive function, mental health and social development.

Adults (18–64 Years)

Adults should accumulate at least 150–300 minutes of moderate-intensity aerobic activity per week, or 75–150 minutes of vigorous-intensity aerobic activity, or an equivalent combination of both. Moderate-intensity activities include brisk walking, recreational swimming, cycling on level terrain and doubles tennis; vigorous activities include jogging, fast cycling, aerobic dance, competitive sports and heavy gardening.

Aerobic activity should be performed in bouts of at least 10 minutes (though recent updates emphasize that any duration counts). Spreading activity across the week — for example, 30 minutes on five days — is more sustainable than cramming it into one or two sessions.

In addition, muscle-strengthening activities involving all major muscle groups should be done on 2 or more days per week. These include resistance training with weights or bands, body-weight exercises (push-ups, squats), heavy lifting and yoga.

These guidelines reduce the risk of cardiovascular disease, type 2 diabetes, certain cancers, depression and premature mortality. They also improve musculoskeletal health, functional capacity and quality of life.

Older Adults (65 Years and Above)

The baseline recommendation for older adults is the same as for younger adults: at least 150–300 minutes of moderate aerobic activity or 75–150 minutes of vigorous activity per week, plus muscle-strengthening on 2 or more days.

However, older adults should also do varied multicomponent physical activity that emphasizes functional balance and strength training on 3 or more days per week. Multicomponent activity combines aerobic, muscle-strengthening, balance and flexibility exercises in a single session — examples include tai chi, yoga, dance-based programs and circuit training designed for seniors.

The balance and strength components are critical for preventing falls, which are a leading cause of injury, disability and loss of independence in this age group. Exercises that challenge balance include standing on one leg, heel-to-toe walking, and dynamic movements that shift the center of gravity.

Older adults with chronic conditions should be as physically active as their abilities and conditions allow, adjusting intensity and type under professional guidance. Even those with mobility limitations benefit from seated exercises, water-based activity and gentle stretching. …