Journal of Strength and Conditioning Research, 2003, 17(4), 822±831 q 2003 National Strength & Conditioning Association Brief Review Effects of Creatine Supplementation and Resistance Training on Muscle Strength and Weightlifting Performance ERIC S. RAWSON1 AND JEFF S. VOLEK2 1Department of Exercise Science and Athletics, Bloomsburg University, Bloomsburg, Pennsylvania 17815; 2Department of Kinesiology, University of Connecticut, Storrs, Connecticut 06269. ABSTRACT Introduction Creatine monohydrate has become the supplement of choice for many athletes striving to improve sports performance. ince 1993, over 200 studies examining the effects of Recent data indicate that athletes may not be using creatine as a sports performance booster per se but instead use cre- Screatine supplementation on exercise performance atine chronically as a training aid to augment intense resis- have been published, and in a consensus statement the tance training workouts. Although several studies have eval- American College of Sports Medicine (ACSM; 53) con- uated the combined effects of creatine supplementation and cluded that, ``exercise performance involving short pe- resistance training on muscle strength and weightlifting per- riods of extremely powerful activity can be enhanced, formance, these data have not been analyzed collectively. especially during repeated bouts...''bycreatine sup- The purpose of this review is to evaluate the effects of cre- plementation. Thus, under the right conditions, crea- atine supplementation on muscle strength and weightlifting tine supplementation can be an effective performance performance when ingested concomitant with resistance training. The effects of gender, interindividual variability, enhancer (53). However, it could be argued that ath- training status, and possible mechanisms of action are dis- letes are not using creatine as a performance booster cussed. Of the 22 studies reviewed, the average increase in per se but instead use creatine as a training aid during muscle strength (1, 3, or 10 repetition maximum [RM]) fol- periods of intense resistance training (18, 25, 28, 42, lowing creatine supplementation plus resistance training 43). The ACSM consensus also states ``creatine sup- was 8% greater than the average increase in muscle strength plementation is associated with enhanced accrual of following placebo ingestion during resistance training (20 vs. strength in strength-training programs.'' Athletes 12%). Similarly, the average increase in weightlifting perfor- mance (maximal repetitions at a given percent of maximal hope that ingesting creatine concurrent with progres- strength) following creatine supplementation plus resistance sive resistance training, and over prolonged periods of training was 14% greater than the average increase in time, will augment their workouts, resulting in in- weightlifting performance following placebo ingestion dur- creased muscle strength and improved weightlifting ing resistance training (26 vs. 12%). The increase in bench performance (maximal repetitions at a given percent press 1RM ranged from 3 to 45%, and the improvement in of maximal strength) in the weight room. The as- weightlifting performance in the bench press ranged from sumption is that the ``bene®ts'' acquired with the as- 16 to 43%. Thus there is substantial evidence to indicate that creatine supplementation during resistance training is more sistance of creatine in the weight room will translate effective at increasing muscle strength and weightlifting per- into improved performance on the playing ®eld. formance than resistance training alone, although the re- Although several studies have evaluated the com- sponse is highly variable. bined effects of creatine supplementation and resis- tance training on muscle strength and weightlifting Key Words: creatine monohydrate, strength training, performance, and athletes are reportedly ingesting cre- nutritional supplement, ergogenic aid, phosphocrea- atine chronically during progressive resistance train- tine ing programs, these data have not been analyzed col- Reference Data: Rawson, E.S., and J.S. Volek. Effects of lectively. With that in mind, it is the purpose of this creatine supplementation and resistance training on review to evaluate the effects of creatine supplemen- muscle strength and weightlifting performance. J. tation on muscle strength and weightlifting perfor- Strength Cond. Res. 17(4):822±831. 2003. mance in young healthy men and women when in- gested concomitant with resistance training. 822 Creatine Supplementation and Resistance Training 823 Prevalence of Creatine Supplementation 3RM bench press, etc.) and/or weightlifting perfor- mance (e.g., number of bench press repetitions at 80% In recent years creatine monohydrate has become the 1RM) had to be reported; and (c) there was a placebo supplement of choice for many athletes who are striv- group that performed the same resistance training ing to increase strength, gain weight, or enhance program. One study that compared 2 groups matched sports performance. Recent surveys indicate that cre- on supplemental carbohydrate and nitrogen intake atine use ranges from 28 to 41% in the National Col- (creatine plus carbohydrate vs. protein plus carbohy- legiate Athletic Association (NCAA), and that athletes drate) was excluded (52), and 1 study that only pro- from 17 different NCAA sports reportedly use creatine vided change scores (27) was included in the table for (18, 28). A survey of 229 members of military or civil- the reader's bene®t, but not in the overall calculations ian health clubs conducted by Sheppard et al. (42) re- described in this review. There were no restrictions set ported that 29±57% (military vs. civilian) of members on the duration of the supplementation regimen, the are creatine users. Creatine use in power sport athletes duration of the resistance training program, the design may be even more prevalent, with 45 to 74% of pow- or volume of the resistance training program, training erlifters, boxers, weightlifters, and track and ®eld ath- experience, or gender of the subjects. Studies that in- letes reportedly using the supplement (41, 43). Crea- vestigated the effects of creatine supplementation dur- tine use is not limited to adults; adolescents are using ing resistance training in older subjects were excluded creatine supplements as well. In a survey of 37 public (4, 8), because few data on the bene®ts of creatine in- high schools in Wisconsin, McGuine et al. (30) report- gestion in older subjects are available and the ®ndings ed that 16.7% of high school student-athletes use cre- have been discrepant (14, 37±39, 58). From the studies atine, and that creatine use increases throughout high that were included in this review, only data on muscle school (9th grade, 8.4% creatine users; 12th grade, strength during weightlifting or weightlifting perfor- 24.6% creatine users). In high school football players, mance are reported. We did not examine the in¯uence 30% of survey respondents reported creatine use, and, of creatine dosage in this review, as it is unlikely that as when all high school sports are combined, the pat- any of the studies included were confounded by pro- tern of increased creatine use throughout high school viding doses of creatine insuf®cient to increase muscle persisted in football as well (9th grade, 10.4% creatine creatine stores. As the purpose of this review was to users; 12th grade, 50.5% creatine users; 31). focus on the effects of creatine supplementation and Sheppard et al. (42) reported that periods of crea- concurrent resistance training on muscle strength and tine use averaged 40 weeks in health club members. weightlifting performance, exercise performance mea- Stanton and Abt (43) reported creatine supplementa- sures such as those obtained from isokinetic, jumping, tion protocols ranging from 4 to 56 days (loading or cycling performance tests are not included in this phase) and from 14 to 91 days (maintenance phase) in review. powerlifters. Juhn et al. (25) surveyed 52 NCAA ath- Twenty-two studies met our inclusion criteria (Ta- letes (aged 18±23 years) and reported that baseball and ble 1). The studies ranged from 7 to 91 days and in- football players ingest creatine for 5 and 3 months, volved only male subjects (17 studies), only female respectively, and most often ingest it in the off-season. subjects (3 studies), or both male and female subjects This is the time of year when athletes spend the most (2 studies). Supplementation protocols ranged from 20 time performing progressive resistance training in an to 25 g of creatine per day for the entire supplemen- attempt to increase strength and/or body mass for the tation period, loading doses of creatine were for 3±7 upcoming competitive season. When surveyed about days, followed by a maintenance dose for the remain- the perceived bene®ts of creatine ingestion, athletes of- der of the supplementation period and lower doses (5 ten cited increased strength (46±92%), increased mus- g´d21, 0.09 g´kg21´d21) of creatine for the entire supple- cle size (55±85%), weight gain (27±47%), and quicker mentation period. The majority of studies used 1RM recovery (81%; 18, 28, 42, 43). Thus, there is evidence testing of large muscle group exercises (e.g., bench that athletes are not ingesting creatine acutely to di- press and squat) and smaller muscle group exercises rectly improve sports performance, but are instead us- (leg extension, arm curls, etc.). Several studies also as- ing the supplement chronically