Any landscaping or gardening activity with a special focus on activating the core and using good form. I also like to throw objects in nature for plyometric training- safety is always a priority with unconventional training. The right tree branch can be used as a pullup bar, and a small log can be used as a lever for barbell “jammers” (pushing it up with your shoulders) don’t overdo it! It’s hard to tell how much weight you are lifting and remember to use good form when you’re not in the gym. It’s also important to have a spotter and start small if you are lifting anything in the wild.