Hydration needs increase in hot weather due to elevated sweat rates, which help regulate body temperature. It's essential to replace lost fluids to prevent dehydration, which can lead to fatigue, heat exhaustion, and impaired performance. Recommendations include drinking water before, during, and after physical activities, as well as monitoring urine color for hydration status. Consuming electrolyte-rich beverages can also be beneficial in extreme heat conditions. Staying mindful of hydration levels ensures better health and optimal performance when exercising in warm environments.