Yes, the trend in the States is toward jungle gym type things and cardio type fitness machines for inmate fitness.
There is/was actually a rule in federal prisons that no money was to be taken from the prison's recreational budget for new weightlifting, karate, or boxing equipment. Many states (particularly on the west coast) tend to have a similar stance. The east coast states, particularly the ones close to York Barbell, are more lenient on the issue.