Make sure you eat healthy and exercise. Eating healthy gets you the nutrients you need to exercise and build strength. Having protein before and after helps give you more energy and build more muscle. Hiking improves your strength a lot because it is usually uphill and uses all leg muscles. I think it works out your core too. Going to the gym or doing planks, push-ups, and sit-ups can help build arm muscles and core muscles. Hope this helps! ;)