When you think HIIT or interval training of any sort, what do you expect it to be? Speeding through burpees and sprints? Well there are lots of different ways to do intervals and they can include strength/weights as well as simple bodyweight cardio exercises such as jacks. Intervals can be done with low or high impact, varying timings or format. Take a look at some of these options. Find one that fits you and add it into a weekly plan.