Martha was tired and covered in muck, and was still resonating inside with the adrenaline gunfire always brought. Jenny, Generated Anomaly, was dead, and he was taking it hard. The Doctor had set the TARDIS in motion and slipped away, leaving Donna and Martha to look at each other across the console. Then, almost at the same time, they turned and left the console room too.
Martha wandered around. She considered going to her room, but after a moment dismissed it. So she took a shower and changed out of her muddy clothes, covered in poison air and Hath blood, and set out for the gym. She'd discovered it by accident when she'd been after the library once, and now she wanted to do something she hadn't in a long time- she wanted to shoot some hoops.
It seemed the TARDIS wanted to help. because the gym had somehow mysteriously materialized in the next hallway over. The hoops were swung down from the ceiling, and there was a rack of pumped up balls in the corner. Martha grinned and patted the wall, then hurried over, quickly losing herself in the rhythmic bounce bounce as she dribbled, the squeak of her shoes on the hardwood floor, and the soft swish as her ball slipped through the hoop. It wasn't till she heard a low whistle that she realized she wasn't alone.
"You're not half bad," Donna commented, strolling onto the court. She was still dressed in her clothes from earlier, but she was wearing trainers now and her hair was tied away from her face. She grinned and plucked up a ball, tossing it back and forth between her hands. "Bet I'm better."
Martha raised an eyebrow and, seeing the teasing glint in Donna's eye, stood straighter. She held her hands out for the ball, and before she knew it, they were racing up and down the court, shoes squeaking as the feinted, scored baskets, and took foul shots as needed. By the time they stopped, they were bent over and panting hard, and Martha didn't think she'd laughed so hard in a long time.
"Didn't know you liked basketball," she commented as they made their way to the showers. Donna laughed and nudged her with an elbow.
"There's a lot you don't know about me, sunshine."
And when the Doctor came looking for them later, he found the TARDIS idling somewhere high above a colorful supernova, both of his companions sitting slumped against the open doors, legs hanging out, chatting about their school days.