kids recumbent bike LISS Cardio
https://www.slideshare.net/x8kujia153/dont-buy-into-these-trends-about-liss-cardio
Even the ideal exercise bicycles Liss cardio are less bulky than a treadmill or some crosstrainer, plus so you'd swerve the travel to and from the gymnasium (time efficient for anyone who have busy schedules) or