Figure 4From: Effect of muscle load tasks with maximal isometric contractions on oxygenation of the trapezius muscle and sympathetic nervous activity in females with chronic neck and shoulder pain Change in the LF/HF ratio of heart rate variability. AUC: area under the curve. MAX 1~MAX 3: the trapezius muscles contract with maximum effort for 1 min. Relax 1~Relax 3: the trapezius muscles relax for 2 min . Values are presented as mean, SE. †, different from the LF/HF ratio first rest (p < 0.01). *, **, different from the LF/HF ratio of the control group (p < 0.05, p < 0.01).Back to article page