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Professor Kojiro Ishi: With global temperatures rising due to global warming, the risk of heat strokes has increased, that is particularly troubling for athletes in competitive sports like tennis.

Rafael Nadal, a member of the famous Big 3 triumvirate in tennis, is a notable example of this reality, when he suffered a heat stroke and reportedly lost 4 kgs, during the Australian Open semi-finals in 2022.

Tennis matches are played on hard, sand-filled artificial grass, and clay courts.