I am not a huge fan of using partial reps, but will use them sparingly with experienced lifters to “through a wrench into their workout”. When I prescribe them they are performed after the client has already reached momentary concentric failure during a set. But, because partial reps place such high demands on the recovery ability of the muscles being worked, I caution against using them more than once every 4 workouts per body part. In reference to this belief, I received an email from an intermediate lifter claiming a study (J Strength Cond Res, 2004, 18(3), 518-521) proved partial reps should be incorporated in his workout instead of full range reps.?

I did a little research, as always, and found the study the gentleman was referencing. This study was conducted over a 10-week period using the bench press as the criterion measurement. Subjects were divided into three groups. Group one trained with full range of motion sets. Group two trained with partial range of motion sets. A partial range of motion was defined as two to five inches from full extension of the elbows. Group three trained with a combination of both partial and full range reps. All groups were pre and post-tested with a full range of motion one rep maximum. No differences were found between the groups. So should we or shouldn’t we use partial reps?

There are several problems I find with this study that are common to many studies trying to illuminate the most efficacious training principles. First, and perhaps most important, inexperienced, recreational subjects were used. Inexperienced subjects can achieve gains in the first few months on just about any program. Second, the length of time the study was conducted was entirely too short. six, eight or, like this study, 10 weeks is just not enough time to show the efficacy of a particular training protocol. And third, the intensity of the exercises or perceived exertion is not mentioned or monitored. Are the subjects going to failure on their sets? Are some subjects pushing themselves harder than others? Are the subjects training in the same manner on exercises other than the bench press? This study like most training studies shows nothing.