Table 2.

Participants and intervention characteristics of the studies included with the systematic review.

Level of participants	Professional		2 studies [16,31]
	Amateur		7 studies [14,20,23,24,30,32,33]
	Untrained		2 studies [15,34]
Type of l-Carnitine	l-Carnitine		6 studies [14,16,20,24,31,33]
	l-Carnitine L-Tartrate		3 studies [15,23,30]
	Glycine-Propionyl l-Carnitine		2 studies [32,34]
Time of administration	Chronic	4 weeks	1 study [30]
		8 weeks	1 study [34]
		9 weeks	1 study [33]
		24 weeks	2 studies [15,23]
	Acute	7 days	1 study [14]
		Before/during	5 studies [16,20,24,31,32]
Doses used	Chronic	1 g/day (Propionyl l-Carnitine)	1 study [34]
		2 g/day	2 studies [30,33]
		2,72 g/day	1 study [23]
		3 g/day (Propionyl l-Carnitine or l-Carnitine)	2 studies [15,34]
	Acute	3 g (l-Carnitine) 3 g (Propionyl l-Carnitine)	3 studies [16,24,31] 1 study [32]
		4 g (l-Carnitine)	3 studies [14,16,20]