Go to any gym and you’ll likely see a row of weight benches lining the mirrored walls. They look like a great place to check your form while doing arm exercises, or maybe to sit and sip some water ...

Box jumps: Pick a stable surface that you can jump onto and land safely (use a step, bench in the gym, low wall outside, etc). Start in a squat and jump from both feet to land on both feet in a squat ...