Table 2.

The mean (SD) ratings of perceived exertion among exercises

Exercise	Ratings of Perceived Exertion a
Prone on ball with right hip extension	13.1 (1.4)—somewhat hard
Prone on ball with left hip extension	13.1 (1.4)—somewhat hard
Prone bridge (plank) on ball	11.8 (1.6)—fairly light
Prone bridge (plank) on toes	11.9 (1.7)—fairly light
Prone bridge (plank) on knees	8.9 (2.1)—very, very light
Side crunch on ball	11.2 (2.2)—fairly light
Side bridge (plank) on toes	11.2 (2.2)—fairly light
Side bridge (plank) on knees	9.9 (2.0)—very light
Crunch	10.2 (2.2)—very light
Bent-knee sit-up	10.4 (2.5)—very light

^aBased on the following scale: 6, no perceived exertion; 7, very, very light; 9, very light; 11, fairly light; 13, somewhat hard; 15, hard; 17, very hard; 19, very, very hard; and 20, maximum perceived exertion.