Table 1.

Potential advantages and shortcomings of the Global Positioning System (GPS) technique used for gait analysis

Advantages	Shortcomings
Available anywhere on the earth in any weather conditions for outdoor measurements at no cost	High cost of professional equipment
Tri-dimensional positioning with centimeter accuracy (Real Time Kinematics, RTK mode)	Not fully validated for gait analysis yet
No space restriction: freedom in the path selection, including uphill/downhill locomotion.	Limited time windows (2–4 h per day)
Free living conditions, i.e close to real life	One body segment measured only (head): Because of mandatory constant satellite access, the antenna must not be obstructed by body parts.
Unlimited number of consecutive strides: limited only by the memory capacity of the receiver and the duration of the batteries.	Outdoor analysis: difficult to standardize environmental conditions (weather, terrain).
	Not fully miniaturized (cumbersome antenna).