When we are standing, the pressure on the intervertebral discs of the lower back is fairly low, much lower than when we sit unsupported. However, standing uses about 20% more energy than sitting, so we get tired more quickly and look to sit down.¹

Being in one position too long induces static muscle exertion, which inhibits blood flow. Consequently, the muscles become fatigued, which causes an antsy, anxious feeling that induces the need to exercise the muscles.⁵

The natural response to the antsy feeling from static muscle fatigue is to fidget, which usually entails automatically shifting postures within the chair. However, these minor postural changes typically do not provide adequate increases in blood flow to relieve the fatigued muscles.⁵

Static muscle fatigue is relieved only through muscle movement. Standing and walking increases the blood flow to fatigued muscles and re-energizes them. People need to get out of their chairs and move at least 5 minutes per hour to minimize that antsy feeling.¹

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