No, most sports drinks do not contain a high amount of sugar or high fructose corn syrup. Gatorade has about the same amount of sugar as whole milk, while 100% apple juice or Sunny Delight contains twice that amount of sugar. In January 2010, Gatorade removed high fructose corn syrup from both its Gatorade and G2 beverages. The taste remains largely unchanged.
While an excessive amount of sugar is harmful, sugars and carbohydrates can provide essential fuel for the body when your muscles work hard. In small amounts, this sugar can help increase fluid absorption for faster rehydration.