Adjustable Weighted Vest

The main feature of vests is that they distribute weight evenly across the front and back, allowing you to maintain a more or less normal posture and gait. When wearing a backpack, you tend to lean forward to counteract the weight behind you. Based on studies of running posture, Rooney and his co-authors suggest that this forward lean may cause you to burn extra energy. Indeed, a classic 1971 study found that carrying 66 pounds of granite fragments in a vest burned 9% less energy than carrying the same weight in a backpack.

This doesn't mean a vest is always the most effective choice. If your load is heavy, placing it in front of you can hinder your movement and vision. There is intense debate over which carrying method is better for your back. If you're on a march, you can choose whatever feels best-though a backpack can help you burn more calories. On the other hand, for tactical personnel, the choice likely depends on your gear.

Calculating the calories required to transport cargo

People have long sought to find a formula to calculate how many calories are burned while hiking at a given speed and with a given load, dating back to military research in the 1970s. The basic idea is to have a group of people carry different weights at different speeds, measure the energy they expend (by measuring the amount of oxygen and carbon dioxide they inhale and exhale), and then perform some statistical analysis to derive the optimal formula.