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Duplanty, AA, Budnar, RG, Luk, HY, Levitt, DE, Hill, DW, McFarlin, BK, Huggett, DB, and Vingren, JL. Effect of acute alcohol ingestion on resistance exercise-induced mTORC1 signaling in human muscle. J Strength Cond Res 31(1): 54-61, 2017-The purpose of this project was to further elucidate the effects postexercise alcohol ingestion. This project had many novel aspects including using a resistance exercise (RE) only exercise design and the inclusion of women. Ten resistance-trained males and 9 resistance-trained females completed 2 identical acute heavy RE trials (6 sets of Smith machine squats) followed by ingestion of either alcohol or placebo. All participants completed both conditions. Before exercise (PRE) and 3 (+3 hours) and 5 (+5 hours) hours postexercise, muscle tissue samples were obtained from the vastus lateralis by biopsies. Muscle samples were analyzed for phosphorylated mTOR, S6K1, and 4E-BP1. For men, there was a significant interaction effect for mTOR and S6K1 phosphorylation. At +3 hours, mTOR and S6K1 phosphorylation was higher for placebo than for alcohol. For women, there was a significant main effect for time. mTOR phosphorylation was higher at +3 hours than at PRE and at +5 hours. There were no significant effects found for 4E-BP1 phosphorylation in men or women. The major findings of this study was that although RE elicited similar mTORC1 signaling both in men and in women, alcohol ingestion seemed to only attenuate RE-induced phosphorylation of the mTORC1 signaling pathway in men. This study provides evidence that alcohol should not be ingested after RE as this ingestion could potentially hamper the desired muscular adaptations to RE by reducing anabolic signaling, at least in men.

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The purpose of this observational study was to determine the circulating leukocyte subset response to completing the 2013 Hotter'N Hell Hundred recreational 164-km road cycle event in a hot and humid environmental condition. Twenty-eight men and four women were included in this study. Whole blood samples were obtained 1-2 hours before (PRE) and immediately after (POST) the event. Electronic sizing/sorting and cytometry were used to determine complete blood counts (CBC) including neutrophil, monocyte, and lymphocyte subsets. The concentration of circulating total leukocytes (103·µL-1) increased 134% from PRE to POST with the greatest increase in neutrophils (319%, p<0.0001). Circulating monocytes (including macrophages) increased 24% (p=0.004) and circulating lymphocytes including B and T cells increased 53% (p<0.0001). No association was observed between rolling time or relative intensity and leukocyte subset. Completing the Hotter n' Hell Hundred (HHH), a 100 mile recreational cycling race in extreme (hot and humid) environmental conditions, induces a substantial increase in total leukocytes in circulation. The contribution of increases in specific immune cell subsets is not equal, with neutrophils increasing to greater than 4-fold starting values from PRE to POST race. It is likely that exercise in stressful environmental conditions affects the complement of circulating immune cells, although activational state and characterization of specific leukocyte subsets remains unclear. The observed increase in circulating cell sub-populations suggests that the circulating immune surveillance system may be acutely affected by exercise in hot and humid conditions.

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This study investigated the acute endocrine responses to a 164-km road cycling event in a hot environment. Thirty-four male experienced cyclists (49.1 ± 8.3 years, 86.8 ± 12.5 kg, 178.1 ± 5.1 cm) participating in a 164-km road cycling event were recruited. Blood samples were collected within 0.3-2.0 h before the start (PRE: ~0500-0700 h) and immediately following the ride (POST). Samples were analysed for testosterone, growth hormone (GH), cortisol and interleukin-6 (IL-6). The temperature and humidity during the event were 35.3 ± 4.9°C and 47.2 ± 14.0%, respectively. Based on the finishing time, results for the fastest (FAST, 305 ± 10 min) and the slowest (SLOW, 467 ± 31 min) quartiles were compared. At POST, testosterone concentration was significantly (P < 0.05) lower (PRE, 20.8 ± 8.6; POST, 18.2 ± 6.7 nmol · L(-1)), while GH (PRE, 0.3 ± 0.1; POST, 2.3 ± 0.3 µg · L(-1)), cortisol (PRE, 661 ± 165; POST, 1073 ± 260 nmol · L(-1)) and IL-6 (PRE, 4.0 ± 3.4; POST, 22.4 ± 15.2 pg · mL(-1)) concentrations were significantly higher than those at PRE. At POST, GH and cortisol were significantly higher for the FAST group than for the SLOW group (GH, 3.6 ± 2.0 and 1.0 ± 0.8 µg · L(-1); cortisol, 1187 ± 209 and 867 ± 215 nmol · L(-1)). Participation in an ultra-endurance road cycling event in a hot environment induced significant acute changes in concentrations of circulating hormones, with a greater augmentation of GH and cortisol in those completing the ride fastest.

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PURPOSE: To examine the effect of post-resistance exercise alcohol ingestion on lipopolysaccharide (LPS)-stimulated production of IFNγ, TNF-α, IL-1ß, IL-6, IL-8, and IL-10. METHODS: Recreationally resistance-trained men (n = 10, 25 ± 3 year, 177 ± 7 cm, 83.8 ± 15.7 kg, 14.8 ± 8.5% body fat) and women (n = 8, 23 ± 2 year, 161 ± 3 cm, 59.5 ± 6.0 kg, 26.5 ± 3.0% body fat) completed two identical heavy back squat sessions (6 × 10 at 80% 1 repetition maximum) followed by ingestion of either an alcohol (ALC; 1.09 g ethanol · kg fat-free mass(-1)) or water (PLA) drink. Blood samples were collected before exercise (PRE), and at 3 h (3 h), and 5 h (5 h) after exercise, stimulated with LPS, and analyzed for IFNγ, TNF-α, IL-1ß, IL-6, IL-8, and IL-10 concentrations. RESULTS: There were no drink conditions by time effects for IFNγ, TNF-α, IL-1ß, or IL-10. Regardless of condition, resistance exercise induce an increase in IFNγ, TNF-α, and IL-1ß at 5 h compared to PRE but a decrease in IL-10 at 3 and 5 h compared to PRE. For ALC, IL-8 was reduced at 5 h compared to PLA. From PRE to 3 h, IL-6 was reduced for ALC but increased for PLA; resistance exercise induced an increase in IL-6 for both conditions at 5 h. CONCLUSIONS: Heavy resistance exercise increased production of IFNγ, TNF-α, IL-1ß, and Il-6 and decreased production of IL-10. Alcohol ingestion after resistance exercise affected aspects of inflammatory capacity (IL-6 and IL-8 production). It appears that some of the effects previously observed for alcohol ingestion alone on the LPS-stimulated cytokine production were overwhelmed by the response to resistance exercise.

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The purpose of this investigation was to examine the acute hormonal response to the kettlebell swing exercise. Ten recreationally resistance trained men (age, 24 ± 4 years; height, 175 ± 6 cm; body mass, 78.7 ± 9.9 kg) performed 12 rounds of 30 seconds of 16 kg kettlebell swings alternated with 30 seconds of rest. Blood samples were collected before (PRE), immediately after (IP), and 15 (P15) and 30 minutes after exercise (P30) and analyzed for testosterone (T), immunoreactive growth hormone, cortisol (C), and lactate concentrations. Heart rate and rating of perceived exertion were measured at the end of each round. Testosterone was significantly higher (p ≤ 0.05) at IP than at PRE, P15, or P30 (PRE: 28 ± 3; IP: 32 ± 4; P15: 29 ± 3; P30: 27 ± 3 nmol·L). Growth hormone was higher at IP, P15, and P30 than at PRE (PRE: 0.1 ± 0.1; IP: 1.8 ± 1.2; P15: 2.1 ± 1.1; P30: 1.6 ± 1.3 µg·L). Cortisol was higher at IP and P15 than at PRE and P30 (PRE: 617 ± 266; IP: 894 ± 354; P15: 875 ± 243; P30: 645 ± 285 nmol·L). Lactate was higher at IP, P15, and P30 than at PRE (PRE: 1.1 ± 0.5; IP: 7.0 ± 3.0; P15: 4.0 ± 2.7; P30: 2.5 ± 1.8 mmol·L). Heart rate increased progressively from 57 ± 12 at PRE to 170 ± 10 at IP. The exercise protocol produced an acute increase in hormones involved in muscle adaptations. Thus, the kettlebell swing exercise might provide a good supplement to resistance training programs.

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Resistance exercise can acutely increase the concentrations of circulating neuroendocrine factors, but the effect of mode on this response is not established. The purpose of this study was to examine the effect of resistance exercise selection on the acute hormonal response using similar lower-body multijoint movement free weight and machine weight exercises. Ten resistance trained men (25 ± 3 years, 179 ± 7 cm, 84.2 ± 10.5 kg) completed 6 sets of 10 repetitions of squat or leg press at the same relative intensity separated by 1 week. Blood samples were collected before (PRE), immediately after (IP), and 15 (P15) and 30 minutes (P30) after exercise, and analyzed for testosterone (T), growth hormone (GH), and cortisol (C) concentrations. Exercise increased (p ≤ 0.05) T and GH at IP, but the concentrations at IP were greater for the squat (T: 31.4 ± 10.3 nmol·L(-1); GH: 9.5 ± 7.3 µg·L(-1)) than for the leg press (T: 26.9 ± 7.8 nmol·L(-1); GH: 2.8 ± 3.2 µg·L(-1)). At P15 and P30, GH was greater for the squat (P15: 12.3 ± 8.9 µg·L(-1); P30: 12.0 ± 8.9 µg·L(-1)) than for the leg press (P15: 4.8 ± 3.4 µg·L(-1); P30: 5.4 ± 4.1 µg·L(-1)). C was increased after exercise and was greater for the squat than for the leg press. Although total work (external load and body mass moved) was greater for the squat than for the leg press, rating of perceived exertion did not differ between the modes. Free weight exercises seem to induce greater hormonal responses to resistance exercise than machine weight exercises using similar lower-body multijoint movements and primary movers.

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BACKGROUND: Physical activity (PA) levels in schools vary widely, and there is interest in studying how student PA accrual relates to school policy and environmental conditions. School PA policy research, however, is in its infancy and generalizable measurement tools do not exist. We developed and assessed reliability of items on the School Physical Activity Policy Assessment (S-PAPA), an instrument designed to assess school PA policy related to physical education (PE), recess, and other opportunities. METHODS: To develop items, we perused associated literature, examined existing instruments, and consulted school policy makers. For test-retest reliability assessment, 31 elementary school PE teachers completed the survey twice, 14 days apart. RESULTS: S-PAPA uses open-ended, dichotomous, multichotomous, and checklist formatting and has 3 modules: 1) Physical Education (47 items), 2) Recess (27 items), and 3) Other Before, During, and After School Programs (15 items). Responses to more than 95% of items were highly related between Times 1 and 2. Generally, physical education and recess items had fair to substantial levels of agreement, and items about other school PA programs had fair to perfect agreement. CONCLUSIONS: Test-retest results suggest S-PAPA items are reliable and useful in assessing PA policies in elementary schools.

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