A method of testing a substance potentially active in the field of lipolysis comprising: preparing a substrate containing at least one triacylglycerol; placing this substrate in contact with a substance potentially active in the field of lipolysis, and with a lipoprotein lipase, in the presence of a cofactor of lipoprotein lipase, for a period of time sufficient to release at least in part one fatty acid of the triacylglycerol; and determining the capacity of inhibition of the release of the fatty acid resulting from the activity of the lipoprotein lipase, under the action of said potentially active substance, and evaluating the result of the inhibition which is either compared to the result obtained in the absence of the potentially active substance tested or compared with the result obtained in the presence of a known inhibitor acting as reference. Cosmetic and pharmaceutical uses are described.