DB Chapter 211
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
"The Hardest Time of His Death" (界王さまと、がんばる死人孫悟空！, Kaiō-sama to, Ganbaru Shinin Son Gokū!; Literally meaning "Do Your Best with Kaiō-sama, Dead Son Goku!") is chapter 211 of the Dragon Ball manga.
Kaiō says they'll begin training, and asks how long he plans on doing it. Goku doesn't know how long he ran down Serpent Road for, but he knows he ain't got much time left. He explains about the two Saiyans coming to his planet, and he wants to train in the short interval until then. Kaiō decides to check how long it'll be before the Saiyans reach Earth: 158 days. Goku's impressed with the ability, but worried about the short time. Kaiō tells him 158 days is plenty of time. 158 days of training here would be worth thousands of years of training on Earth.
Kaiō says that even still, those two Saiyans possess fierce strength. They're even stronger than him, in fact. Goku freaks out, but Kaiō tells him everything will be okay if he surpasses him. Kaiō decides they should start now, and so he calls for Bubbles. First Goku needs to conquer the gravity on this planet, and he'll have proven himself once he can catch Bubbles.
Bubbles starts running around, and Goku stomps along to follow. Then Goku decides to take off his weighted undershirt, and the wristbands and boots. Now he can run much quicker, and Kaiō notes he's already training with weighted equipment. Goku nearly catches up to Bubbles, and so Bubbles picks up the pace. Goku can't believe this, and then asks Kaiō if he can't have some food. He hasn't eaten in half a year. Kaiō decides to feed him, and says it's rare that a dead person would get hungry.
Goku then empties a few bowls until he's full, and asks Kaiō if he gets bored on such a small planet. Kaiō says his latest hobby is driving around, and then tells him to get back after Bubbles, along with putting his weighted clothing back on. Goku says that'll be so much harder, but Kaiō explains that the Saiyan's planet had the same gravity as this planet. And, the Saiyans were born with an incredible "fighting sense", but Goku says it's okay, because he's also a Saiyan.
Meanwhile, it's night out on Earth, and Gohan's all beaten up. Piccolo says he's finally cured him from being a crybaby. Gohan asks Piccolo if he's ever fought his father, and Piccolo says their fight's not over. After the Saiyans, his father's next. Gohan says his father had mentioned the reborn Piccolo wasn't bad, and Gohan agrees. But his mother and grandfather are still scared of him. Piccolo gets pissed and then yells at him to go to sleep.
And after forty days... Goku finally catches Bubbles, and Kaiō is impressed. He gets excited and thinks Goku will be able to master his sure-to-kill technique, the Kaiō-Ken, in the next 118 days. Kaiō gets fired up and tells Goku it's time to start the rough training. He'll become the best in the universe, the best in the heavens! It'll be good for both the heart and the body! But, first it's time for tea, and Goku falls over. Way over at God's Palace, God tells the five humans they've all become really strong, and there's nothing more they can learn there. And they're all wearing weighted clothes now, too. Piccolo continues training Gohan, and Kaiō trains Goku. "And, the time of the decisive battle has drawn near...!"