This is the 17063rd most frequent Russian word.
спортсмену
"Спортсмену" means "to the athlete" in English.
The word "спортсмену" is used in the dative case to indicate the indirect object receiving the action.
Покажите дорогу к стадиону спортсмену.
Show the way to the stadium to the athlete.
Here, "спортсмену" also appears in the dative case, fulfilling the function of the recipient of the advice.
Мы дали совет спортсмену по улучшению его выступлений.
We gave advice to the athlete on improving his performances.
"Спортсмену" functions in dative case to designate who finds the plan useful.