DBZ Episode 124
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Z Warriors Prepare is the seventh episode of the Trunks Saga and the one hundred twenty-fourth overall episode in the uncut version Dragon Ball Z series. The original Japanese title is "Koeteyaru...Goku wo!! Sento Minzoku Saiya-jin no Ou" (こえてやる...悟空を!! 戦闘民族サイヤ人の王). The episode first aired on January 29, 1992. It's original American air date was September 12, 2000.
Yamcha tries Vegeta's capsule at 300x gravity, nearly getting crushed to death by the extreme gravity. The next day, Vegeta trains so hard, firing the Ki Blast inside the capsule, that it explodes.
Upon hearing the explosion, Bulma rushes out to find Vegeta severely injured. She accompanies him to a hospital, where she displays affection towards the injured Saiyan for the first time. She shows genuine concern for Vegeta and even falls asleep next to his bed. When Vegeta awakes from a nightmare, he wonders why Bulma is next to him. Vegeta resumes his training the very next day in terrible shape. The episode ends with Gohan fighting Goku and Vegeta still training.