Why Do My Arms Feel Heavy After Holding My Newborn Baby for an Hour?
1. Introduction The sensation of profound arm heaviness after holding a newborn baby is the direct result of isometric muscle fatigue, localized lactic acid accumulation, and transient restriction of venous blood flow. Sustaining a static cradling posture for an hour forces the biceps and deltoid muscles to remain in a constant state of contraction, which … Read more