Prolonged standing can cause tiredness, effecting joints such as the ankles and knees, they can tense up and become locked. There is a tendency to shift weight from one side to the other, which increases the release of muscular energy, and in turn, can lead to fatigue. Regular standing in static positions can slowly diminish elasticity in the soft tissues. This degenerative damage can lead to rheumatic diseases.
Research into venous pressure on a group of workers found the pressure was 56mm when seated and 87mm when standing. The pressure dropped to 21mm after taking 10 steps concluding that walking for two to four minutes a day after every 15-minute period of standing was more comfortable than standing without walking (Konz S, Johnson S, Work Design 1-629,2000).