What Kids Should Wear Outdoors in Summer to Reduce Heat Illness Risk

Key facts

In May 2026, the U.S. EPA updated its children's extreme heat guidance and the National Integrated Heat Health Information System hosted a national Heat Safety Week (May 18-22, 2026), with federal agencies identifying clothing choice as a modifiable risk factor for heat illness in children during outdoor summer activities. The American Academy of Pediatrics, in a policy statement reaffirmed in March 2025, named heat-retaining uniforms and protective gear as a leading preventable cause of exertional heat stroke in young athletes. The Alliance for Heat Resilience and Health, a coalition of more than a dozen national organizations including the American Public Health Association and the American Medical Association, reported in its 2026 Heat Safety Awareness Toolkit that extreme heat now kills more Americans than any other weather-related hazard.

• The AAP identifies "inappropriately wearing clothing that plays a role in excessive heat retention" as a primary, modifiable risk factor for exertional heat illness in youth athletes.
• The EPA and CDC both advise dressing children in loose, lightweight, light-colored clothing during outdoor activity in warm weather.
• The 2026 AHRH toolkit notes that 13.2 million U.S. households report being too hot for more than a day, and that children are among the most vulnerable groups due to limited ability to self-regulate temperature and limited agency to remove themselves from heat.
• The CDC-NOAA HeatRisk Dashboard, updated for the 2026 season, provides zip-code-level, seven-day heat forecasts to help families plan outdoor activities safely.

What it means for parents

Summer youth sports leagues and outdoor camps are in full swing across the U.S. and Canada. What children wear to those activities matters more than many parents realize. Federal guidance updated this spring is consistent on one point: every layer of non-breathable fabric covering a child's body reduces the skin's ability to shed heat through sweat evaporation. That includes socks. The feet and lower legs contain a dense network of blood vessels that play a role in thermoregulation. Heavy, thick, or synthetic socks that trap moisture rather than wick it away can raise local skin temperature and contribute to discomfort during prolonged activity.

Parents should also pay attention to the heat index, not just the air temperature. A day that feels like 75 degrees Fahrenheit can still post a dangerous heat index above 90 degrees if humidity is high. The AAP recommends reducing or rescheduling activities lasting more than 15 minutes when the heat index reaches that threshold. For children's sports, this means checking the CDC HeatRisk Dashboard before practice, not just glancing at a weather app.

Background and context

The AAP's clinical position on children and heat stress, originally published in Pediatrics and reaffirmed in March 2025, corrected a long-standing assumption that youth athletes are less heat-tolerant than adults. Research now shows children can thermoregulate as effectively as adults when they are well-hydrated. The primary risk drivers are inadequate hydration, insufficient recovery time, and heat-retaining clothing, all of which are preventable. The AAP explicitly singles out uniforms, pads, and protective equipment as contributors to excess heat load in youth sports, making clothing selection one of the few parent-controlled variables in this equation.

The national profile of this issue grew sharper heading into summer 2026. The NIHHIS Heat Safety Week in May drew participation from state health departments including New York, where the state Department of Health issued a May 18, 2026, public advisory emphasizing that children who exercise outdoors are among the highest-risk groups for heat illness. At the federal level, the EPA's dedicated children's heat health page, refreshed May 22, 2026, lists breathable, loose-fitting clothing as a first-line intervention. The AHRH coalition's 2026 toolkit, published just ahead of the summer season, echoes that guidance and calls for more consistent heat safety policies at schools and youth programs nationwide.

Takeaway

Summer 2026 opens with federal agencies and a broad health coalition aligned on a simple, actionable message: what children wear during outdoor physical activity is a first-line heat illness prevention tool. Light-colored, loose, breathable fabrics from head to toe reduce heat load. For parents outfitting kids for soccer, camp, or backyard play, that means thin, moisture-managing socks as well as breathable tops and shorts. SUNBVE's athletic cotton crew socks are built for active wear, with a reinforced heel and breathable combed cotton construction that pulls sweat away from the skin during exertion.