Table 1. Subject data.

Subject	Gender	Age (yrs)	Mass (kg)	Height (m)	Speed (ms)	Training	Entrainment	Coupling Ratio (s)
1	F	39	54.0	1.57	2.4	Casual	Coupled, vp,vr*	2:1, 3:1
2	F	41	59.4	1.73	2.4	Nonrunner	Coupled	2:1
3	M	35	72.5	1.75	2.9	Nonrunner	Coupled, vr*	3:1, 3.5:1
4	M	43	76.2	1.83	2.4	Nonrunner	Uncoupled*
5	F	43	60.8	1.73	2.6	Casual	Coupled, vp*	2:1
6	F	23	59.0	1.65	2.4	Nonrunner	Coupled, vp*	2:1
7	M	26	86.2	1.78	2.4	Nonrunner	Coupled, vp,vr*	2:1, 2.5:1, 3:1
8	F	41	51.9	1.67	2.4	Casual	Coupled, vp*	2.5:1
9	F	28	64.4	1.70	2.4	Nonrunner	Uncoupled*
10	M	49	71.7	1.78	2.8	Trained	Coupled, vr *	2:1, 3.5:1
11	F	47	62.6	1.65	2.4	Trained	Coupled, vp,vr*	2:1,3:1
12	F	27	59.0	1.75	3.4	Trained	Coupled,vp*	2:1
13	F	25	54.5	1.60	3.4	Trained	Coupled	2:1
14	M	31	79.4	1.83	2.3	Nonrunner	Uncoupled*
	mean	36	65.1	1.72	2.6
	s.e.m.	2	2.8	0.02	0.1

^*Ensemble average calculated for this subject.

Coupling abbreviations: vr  =  variable coupling ratio. vp  =  variable coupling phase relationship.