Recent research has shown dietary nitrate to impart favorable effects on blood flow and exercise. The purpose of this randomized, double-blind, placebo-controlled, crossover study was to investigate the acute effects of pomegranate extract on blood flow, vessel diameter, and exercise performance in active individuals. Nineteen men and women (Mean ± SD; Age: 22.2 ± 2.2 yrs; Height: 174.8 ± 10.7 cm; Body mass: 71.9±13.5 kg) were randomly assigned to a placebo (PL) or pomegranate extract (PE) group. Participants performed a maximal oxygen consumption treadmill test to determine peak velocity (PV). Participants returned after 24–48 hours, and ingested either PL or PE. Brachial artery blood flow was assessed using ultrasound at baseline and 30 minutes post-ingestion (30minPI). Three treadmill runs to exhaustion (TTE) were performed at 90%, 100%, and 110%PV. Blood flow was assessed immediately after each exercise bout and 30 minutes post-exercise (30minPEx). After a 7–10 day washout, participants repeated the same procedures, ingesting the opposite supplement. Separate repeated measures ANOVAs were performed for blood flow, vessel diameter, and TTE. Blood flow was significantly augmented (p=0.033) 30minPI with PE in comparison to PL. Vessel diameter was significantly larger (p=0.036) 30minPEx with PE. Ingestion of the PE was found to significantly augment TTE at 90% (p=0.009) and 100% PV (p=0.027). Acute ingestion of PE 30 min prior to exercise may enhance vessel diameter, blood flow, and delay fatigue during exercise. Results of the current study indicate that PE is ergogenic for intermittent running, eliciting beneficial effects on blood flow.

The effects of pomegranate extract (PE) supplementation were evaluated on high-intensity exercise performance, blood flow, vessel diameter, oxygen saturation (SPO2), heart rate (HR), and blood pressure (BP). In a randomized, crossover design, nineteen recreationally resistance trained participants were randomly assigned to PE (1000 mg) or placebo (PL), which were consumed 30 min prior to a repeated sprint ability (RSA) test and repetitions to fatigue (RTF) on bench and leg press. The RSA consisted of ten six-second sprints on a friction-loaded cycle ergometer with 30 s recovery. Brachial artery blood flow and vessel diameter were assessed by ultrasound. Blood flow, vessel diameter, SPO2, HR, and BP were assessed at baseline, 30 min post ingestion, immediately post exercise (IPost), and 30 min post exercise (30minPost). With PE, blood flow significantly increased IPost RSA (mean difference [MD]=18.49 mL·min−1; P<0.05), and IPost and 30minPost RTF (P <0.05) according to confidence intervals (CI). Vessel diameter increased significantly 30minPost RSA according to CI and resulted in a significant interaction IPost and 30minPost RTF (P <0.05). With PE, according to CI, average and peak power output increased significantly in sprint 5 of the RSA (P <0.05). There was no significant difference between PE and PL for bench (P =0.25) or leg press (P =0.15) repetitions. Acute PE supplementation enhanced vessel diameter and blood flow, suggesting possible exercise performance enhancement from increased delivery of substrates and oxygen. The acute timing and capsule form of PE may be advantageous to athletic populations due to ergogenic effects, taste, and convenience.

The purpose of this study was to examine muscle characteristics of the vastus lateralis (VL) and body composition of National Collegiate Athletic Association (NCAA) Division I football players. Sixty-nine Division I football players (mean ± SD; age: 20.0 ± 1.1 years; height: 186.2 ± 7.0 cm; body mass: 106.3 ± 21.1 kg; %fat: 17.8 ± 4.6%) were stratified by player position, race, year, and starter status. A panoramic scan of the VL was performed using a GE Logiq-e B-mode ultrasound. Muscle cross-sectional area (mCSA) and echo intensity (EI) were determined using Image-J software from the VL scan. Body composition measures were determined using dual-energy x-ray absorptiometry (DXA). For mCSA, defensive linemen (DL: 46.7 ± 4.2 cm) had significantly greater CSA (p ≤ 0.05) than wide receivers (WR), linebackers (LB), defensive backs (DB), punters/kickers (PK), and running backs (RB). There were no significant differences for EI (p > 0.05) between positions. Offensive linemen and DL had significantly greater %fat than WR, LB, DB, PK, and RB (p ≤ 0.05); greater lean mass than all other positions (p ≤ 0.05); and more fat mass than quarterbacks, WR, LB, DB, PK, and RB (p ≤ 0.05). There were no muscle or body composition differences for race, year, or starter status. Because no differences between positions were observed for EI measures, it may indicate that competitive athletes have increased muscle quality regardless of body composition differences. Ultrasound and DXA measures may be useful to identify muscle characteristics and imbalances if a player gains or loses weight, suffers an injury, or declines in performance.

BackgroundThe purpose of this study was to examine the effect of exercise modality and pre-exercise carbohydrate (CHO) or protein (PRO) ingestion on post-exercise resting energy expenditure (REE) and respiratory exchange ratio (RER) in women.MethodsTwenty recreationally active women (mean ± SD; age 24.6 ± 3.9 years; height 164.4 ± 6.6 cm; weight 62.7 ± 6.6 kg) participated in this randomized, crossover, double-blind study. Each participant completed six exercise sessions, consisting of three exercise modalities: aerobic endurance exercise (AEE), high-intensity interval running (HIIT), and high-intensity resistance training (HIRT); and two acute nutritional interventions: CHO and PRO. Salivary samples were collected before each exercise session to determine estradiol-β-17 and before and after to quantify cortisol. Post-exercise REE and RER were analyzed via indirect calorimetry at the following: baseline, immediately post (IP), 30 minutes (30 min) post, and 60 minutes (60 min) post exercise. A mixed effects linear regression model, controlling for estradiol, was used to compare mean longitudinal changes in REE and RER.ResultsOn average, HIIT produced a greater REE than AEE and HIRT (p < 0.001) post exercise. Effects of AEE and HIRT were not significantly different for post-exercise REE (p = 0.1331). On average, HIIT produced lower RER compared to either AEE or HIRT after 30 min (p < 0.001 and p = 0.0169, respectively) and compared to AEE after 60 min (p = 0.0020). On average, pre-exercise PRO ingestion increased post-exercise REE (p = 0.0076) and decreased post-exercise RER (p < 0.0001) compared to pre-exercise CHO ingestion.ConclusionHIIT resulted in the largest increase in REE and largest reduction in RER.