Ultralight backpacking enthusiasts argue that it's much easier to enjoy the environment with a lighter pack. With less weight on your back, you can look up and enjoy the scenery while you hike, and you'll arrive at camp in the evening more energized. Overall, you'll experience less fatigue, which is good because fatigue is a major factor in many hiking-related injuries. Falling, tripping and twisting an ankle are all more likely to happen when your muscles and your mind are tired. Lighter-weight packs also reduce the stress on your back and legs -- something that can easily lead to injuries.
Another benefit? You'll travel farther each day. Everyone is different, but it's not unusual for backpackers who reduce the weight of their packs by 50 percent to increase the distance they travel by 50 percent. You'll also be able to tackle more rigorous trails. The lighter-weight pack allows you to cruise up and down difficult terrain more easily. If you've got a pack that weighs more than a quarter of your body weight on your back, you won't be "cruising" anywhere.
Many people get nervous when they think about heading into the backcountry in cold weather with minimal gear. But ultralight proponents maintain that with a lighter pack, you're able to hike faster, and the energy you burn winds up keeping you warm. (Although you'll want to be careful you don't sweat too much. A wet layer of clothing will ultimately reduce your body temperature. Read more about that in "How to Avoid Hypothermia".)
Now that you're sold on the sport, let's get packing for your lightweight hike.