Impact of Polyphenol Supplementation on Acute and Chronic Response to Resistance Training

Abstract

Beyer, KS, Stout, JR, Fukuda, DH, Jajtner, AR, Townsend, JR, Church, DD, Wang, R, Riffe, JJ, Muddle, TWD, Herrlinger, KA, and Hoffman, JR. Impact of polyphenol supplementation on acute and chronic response to resistance training. J Strength Cond Res 31(11): 2945–2954, 2017—This study investigated the effect of a proprietary polyphenol blend (PPB) on acute and chronic adaptations to resistance exercise. Forty untrained men were assigned to control, PPB, or placebo. Participants in PPB or placebo groups completed a 4-week supplementation period (phase I), an acute high-volume exercise bout (phase II), and a 6-week resistance training program (phase III); whereas control completed only testing during phase II. Blood draws were completed during phases I and II. Maximal strength in squat, leg press, and leg extension were assessed before and after phase III. The exercise protocol during phase II consisted of squat, leg press, and leg extension exercises using 70% of the participant's strength. The resistance training program consisted of full-body exercises performed 3 d·wk−1. After phase I, PPB (1.56 ± 0.48 mM) had greater total antioxidant capacity than placebo (1.00 ± 0.90 mM). Changes in strength from phase III were similar between PPB and placebo. Polyphenol blend supplementation may be an effective strategy to increase antioxidant capacity without limiting strength gains from training.

Effects of natural polyphenol-rich pomegranate juice on the acute and delayed response of Homocysteine and steroidal hormones following weightlifting exercises: a double-blind, placebo-controlled trial

“…that POMj consumption inhibits Tproduction in 38 normal weight postmenopausal healthy women [78], in 23 patients with Polycystic Ovarian Syndrome [79] and among rats with Benign prostatic hyperplasia [80]. Similarly, our results are in line with recent study in healthy untrained men showing that, compared to PLA, polyphenol supplementation slightly attenuate acute plasma [T] response with no observed effect on [C] response following strength exercise [50]. The exact mechanisms explaining the post-exercise decrease in plasma [T] following POMj intake still not well established [78].…”

“…In order to monitor anabolic/catabolic balance during strength exercise, previous studies have investigated circulating [T] and [C] before and after strength exercises, but the existing findings are inconsistent. Indeed, while [T] increased significantly from pre to post training session in the studies of Weiss et al [67] (ΔT: 22%), Jensen et al [68] (ΔT: 27%), Crewther et al [44] (ΔT: 7%) and Ammar et al [42] (ΔT: 12%), [T] remained unchanged in other reports [50,69,70]. Surprisingly, Hakkinen et al [71] reported that, following successive strength sessions performed in 1 day, [T] may increase, decrease or not change.…”

“…Similarly, divergent findings have been reported for ΔC during strength exercises. Indeed, in response to a high-volume lower body resistance exercises session [50], or a high-intensity weightlifting training session [44], [C] was showed to increase by 11% from pre to post exercise-session [44]. However, following a hypertrophy based-exercises-protocol, [C] decreased significantly (ΔC: − 24.7%) compared to the baseline values [42] which can result in higher post exercises values for [T/C] ratio (+ 60.3%) [42].…”

“…In this context, previous research has reported that 4 weeks consumption of antioxidant nutrients coupled with eccentric training (i.e., using vitamin C and E [88]) or muscular endurance resistance training (i.e., using green tea extract [89]) did not affect gains in isometric strength [88] and did not alter the changes in one repetition maximum [89]. More recently, Beyer et al [50] have provided additional evidence that antioxidant nutrients are less likely to attenuate training adaptation and showed that, flowing a 6-week progressive resistance training program using PLA or polyphenol blend (PPB) supplementation, no significant difference in maximal strength gains was observed between conditions during squat, leg press, and leg extension exercise. The conflicting findings of previous research coupled with the different explanation and interpretation of decreasing post exercise plasma [T] using POMj compared to PLA render the usefulness of antioxidant supplementation during strength training as questionable at this stage.…”

“…Values for α were set at 0.05 and for power at 0.90. Based on the results of Beyer et al [50], effect sizes were estimated to be 0.53 (medium effect). To reach the desired power, data from at least eight participants were deemed to be sufficient to minimize the risk of incurring a type 2 statistical error.…”