4-folds by Forsyth-Sinning for Males is a bodyfat calculation based on 4-folds by Forsyth-Sinning formula. All skinfold measurements should be made on the right side of the body in mm using a body fat caliper. Body fat caliper should be placed 1 cm away from thumb and finger,perpendicular to skinfold,and halfway between crest and base of fold. Pinch should be maintained with the body fat caliper for 1 to 2 seconds before reading the caliper. Take duplicate measurements at each site,allow time for skin to regain normal texture and thickness.
H.L. Forsyth,W. E. Sinning. "The anthropometric estimation of body density and lean body weight of male athletes." Medicine and Science in Sports. 5(3):174-180,1973.