נק' מוניטין:
58,701
The effects of supplementation with P-Synephrine alone and in combination with caffeine on resistance exercise performance
Nicholas A. Ratamess1*, Jill A. Bush1, Jie Kang1, William J. Kraemer2, Sidney J. Stohs3, Vincenzo G. Nocera1, Megan D. Leise1, Keith B. Diamond1 and Avery D. Faigenbaum1
* Corresponding author: Nicholas A Ratamess [email protected]
Author Affiliations
1 Department of Health and Exercise Science, The College of New Jersey, Ewing 08628, NJ, USA
2 Department of Human Sciences, The Ohio State University, Columbus 43210, OH, USA
3 School of Pharmacy and Health Professions, Creighton University, Omaha 68178, NE, USA
Received: 10 April 2015
Accepted: 2 September 2015
Published: 17 September 2015
Abstract
Background
Little is known concerning the potential ergogenic effects of p-synephrine supplementation. Therefore, the purpose of the present study was to examine the effects of supplementation with p-synephrine alone and in combination with caffeine on free-weight resistance exercise performance.
Methods
Twelve healthy, college-aged men performed a control (CT) resistance exercise protocol consisting of 6 sets of squats for up to 10 repetitions per set using 80 % of their one repetition-maximum (1RM) with 2 min of rest in between sets. Each subject was randomly assigned (in double-blind, balanced manner) to a treatment sequence consisting of use of 3 supplements: p-synephrine (S; 100 mg), p-synephrine + caffeine (SCF; 100 mg of p-synephrine plus 100 mg of caffeine), or a placebo (P). For each supplement treatment (separated by 1 week), subjects consumed the supplement for 3 days prior to each protocol and the morning of each protocol, and subsequently did not consume any supplements for 3 days following (i.e. wash-out period). On each protocol day, subjects reported to the lab at a standard time, consumed a supplement, sat quietly for 45 min, performed the resistance exercise protocol, and sat quietly for 30 min post exercise. Performance (repetition number, force, velocity and power), blood lactate, and ratings of perceived exertion (RPE) data were collected during each protocol.
Results
Supplements SCF and S produced a significantly (P < 0.05) greater number of repetitions performed than CT (by 11.0 ± 8.0 %) and P (by 6.0 ± 7.0 %) and a 10.6 ± 12.0 % greater increase in volume load per protocol than CT and P. Most of the differences were seen during the last 3 sets. Mean power and velocity for all 6 sets were significantly higher in SCF compared to CT and P by ~6.2 ± 8.0 %. No supplement effects were observed in RPE or blood lactate, and no adverse side effects were observed or reported.
Conclusions
S and SCF augmented resistance exercise performance (total repetitions, volume load) without increasing blood lactate or RPE. The addition of caffeine in SCF increased mean power and velocity of squat performance. These results indicate supplementation with S and SCF can enhance local muscle endurance during resistance exercise.
Nicholas A. Ratamess1*, Jill A. Bush1, Jie Kang1, William J. Kraemer2, Sidney J. Stohs3, Vincenzo G. Nocera1, Megan D. Leise1, Keith B. Diamond1 and Avery D. Faigenbaum1
* Corresponding author: Nicholas A Ratamess [email protected]
Author Affiliations
1 Department of Health and Exercise Science, The College of New Jersey, Ewing 08628, NJ, USA
2 Department of Human Sciences, The Ohio State University, Columbus 43210, OH, USA
3 School of Pharmacy and Health Professions, Creighton University, Omaha 68178, NE, USA
Received: 10 April 2015
Accepted: 2 September 2015
Published: 17 September 2015
Abstract
Background
Little is known concerning the potential ergogenic effects of p-synephrine supplementation. Therefore, the purpose of the present study was to examine the effects of supplementation with p-synephrine alone and in combination with caffeine on free-weight resistance exercise performance.
Methods
Twelve healthy, college-aged men performed a control (CT) resistance exercise protocol consisting of 6 sets of squats for up to 10 repetitions per set using 80 % of their one repetition-maximum (1RM) with 2 min of rest in between sets. Each subject was randomly assigned (in double-blind, balanced manner) to a treatment sequence consisting of use of 3 supplements: p-synephrine (S; 100 mg), p-synephrine + caffeine (SCF; 100 mg of p-synephrine plus 100 mg of caffeine), or a placebo (P). For each supplement treatment (separated by 1 week), subjects consumed the supplement for 3 days prior to each protocol and the morning of each protocol, and subsequently did not consume any supplements for 3 days following (i.e. wash-out period). On each protocol day, subjects reported to the lab at a standard time, consumed a supplement, sat quietly for 45 min, performed the resistance exercise protocol, and sat quietly for 30 min post exercise. Performance (repetition number, force, velocity and power), blood lactate, and ratings of perceived exertion (RPE) data were collected during each protocol.
Results
Supplements SCF and S produced a significantly (P < 0.05) greater number of repetitions performed than CT (by 11.0 ± 8.0 %) and P (by 6.0 ± 7.0 %) and a 10.6 ± 12.0 % greater increase in volume load per protocol than CT and P. Most of the differences were seen during the last 3 sets. Mean power and velocity for all 6 sets were significantly higher in SCF compared to CT and P by ~6.2 ± 8.0 %. No supplement effects were observed in RPE or blood lactate, and no adverse side effects were observed or reported.
Conclusions
S and SCF augmented resistance exercise performance (total repetitions, volume load) without increasing blood lactate or RPE. The addition of caffeine in SCF increased mean power and velocity of squat performance. These results indicate supplementation with S and SCF can enhance local muscle endurance during resistance exercise.
http://www.jissn.com/content/pdf/s12970-015-0096-5.pdf
