Characteristic Study ID	Measuremet period		Study population		Intervention group	Control group	Overall effect	Comments
Bush 1989	Baseline		431 boys and girls		3	3	NS	Fitness score determined by taking the mean of pulse rate at 1, 2 and 3 min after exercise and assigning score of 1 to 6 (low to high)
	1st year of intervention				3	3	P = 0.437
	2nd year intervention				3	3	P = 0.011
	3rd year intervention				3	3	P = 0.134
	End of intervention (year 4)				3	3	P = 0.596
Ewart 1998	Baseline End of intervention		88 adolescent girls		80 79	84 84	NS	Heart rate recorded by a watch monitor
Luepker 1996	Baseline		4019 boys and girls		87	87	P = 0.61	5 recordings (1 min apart) were obtained for heart rate after a 5 min rest period using the Dinamap automatic blood pressure device. The average of the last 3 readings was used Difficult to determine if positive effect can be attributed to the intervention given no positive results were observed at the end of the intervention
	End of intervention (year 3)				80	79	P = 0.03
McManus 2008	Intervention 1	Baseline	193 boys and girls		83	84	NS	Resting heart‐rate was recorded supine and standing using a Polar S810
		End of intervention (6 months)			83	86
	Intervention 2	Baseline			86	84	NS
		End of intervention (6 months)			83	86
Stephens 1998	Intervention 1	Baseline	90 boys and girls		78	76	NS	Pulse rate: resting
		End of intervention			73	81
	Intervention 2	Baseline			140	144	P < 0.05	Pulse rate: maximal exercise
		End of intervention			125	146
	Intervention 3	Baseline			108	112	P < 0.05	Pulse rate: recovery
		End of intervention			88	123
Walter 1988	Baseline		3388	Westchester	79	78	NS
	End of intervention				78	76
	Baseline			Bronx	77	77	NS
	End of intervention				74	75
CI: confidence interval; NA: not acknowledged; NS: not significant.