Electrolytes, such as sodium, potassium, and magnesium, are significant during physical activity as they help maintain fluid balance and muscle function. They regulate nerve signaling and muscle contractions, which are vital for optimal athletic performance. During intense exercise, electrolytes are lost through perspiration and need to be replenished to prevent dehydration and maintain performance levels. An imbalance can lead to issues such as cramping, fatigue, and dizziness, making it important to consume electrolyte-rich foods or drinks during prolonged activities.