Before Oleksandr Usyk of Ukraine outclassed Anthony Joshua to win their heavyweight championship rematch, Usyk’s manager, Egis Klimas, boasted about credulity-stretching feats of physical output he had seen the Ukrainian boxer perform in training.

He mentioned a six-hour bike ride in the 110-degree (43 degrees Celsius) heat in Saudi Arabia, where Saturday night’s bout took place. And there was a 6-mile (9.6 km) swim. Another day, Klimas said, Usyk held his breath under water for five minutes.

Klimas clearly wanted to impress reporters with Usyk’s prowess and warn everyone present — Joshua included — that the 35-year-old Usyk, previously a world champion at cruiserweight, possessed deep physical and mental reserves.