I agree with what the previous guys have stated. Pushing heavy weight is great for training for the back country. One thing I would add is with heavy weight training, make sure to keep your muscles stretched and moving well. I come from the bodybuilding side of things, so I pack a lot more lbs on my frame than most in the back country. Even with the extra weight and 4 knee surgeries later, I can still truck it. But I do keep up on stretching and foam rolling. The foam roller has been a game changer. Keeps my legs moving well and from getting so tight. Unfortunately a lot of us sit for work, and that leads to getting really tight in our legs and hips, which causes issues when hiking. I'd say go for the weight training, but also build in some recovery and stretching work.