Table 1.

Table of estimates of the fixed effect on muscle workload, linear rate of fatigue with the halo-type structure compared with without the halo-type structure

Muscle	Parameter	b	Error	df	t	P values	95% CI
							Lower	Upper
LSCM	Workload	0.52	0.22	40 097	2.31	0.021	0.08	0.96
	Linear fatigue	−3.57	0.39	40 097	−9.19	0.001	−4.34	2.81
LCES	Workload	7.06	0.60	40 097	11.76	0.001	5.88	8.24
	Linear fatigue	−68.34	5.20	40 097	−13.14	0.001	−78.53	−58.15
	Quadratic fatigue	140.85	12.08	40 097	11.66	0.001	117.16	164.52
	Cubic fatigue	−87.14	7.94	40 097	−10.98	0.001	−102.71	−71.57
RSCM	Workload	6.78	0.23	40 097	29.89	0.001	6.33	7.22
	Linear fatigue	−0.86	0.39	40 097	−2.19	0.029	−1.63	−0.09
RCES	Workload	0.54	0.38	40 097	1.41	0.16	.21	1.28
	Linear fatigue	−5.26	1.76	40 097	−2.99	0.003	−8.71	−1.81
	Quadratic fatigue	−0.36	1.70	40 097	−0.21	0.831	−3.71	2.98

Quadratic and cubic rates of fatigue are shown where log likelihood tests indicated a better fit for models including these trends.

‘b’ is the estimate of the fixed effect. ‘Error’ is the SE. ‘t’ is the t-statistic for the fixed effect. ‘P’ is the significance of the effect. ‘95% CI’ is the 95% CI for the fixed effect.

LCES, left cervical erector spinae; LSCM, left sternocleidomastoid; RCES, right cervical erector spinae; RSCM, right sternocleidomastoid.