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1.
Nutrients ; 15(13)2023 Jun 22.
Article in English | MEDLINE | ID: mdl-37447166

ABSTRACT

Human nutrition, and what can be considered "ideal" nutrition, is a complex, multi-faceted topic which many researchers and practitioners deliberate. While some attest that basic human nutrition is relatively understood, it is undeniable that a global nutritional problem persists. Many countries struggle with malnutrition or caloric deficits, while others encounter difficulties with caloric overconsumption and micronutrient deficiencies. A multitude of factors contribute to this global problem. Limitations to the current scope of the recommended daily allowances (RDAs) and dietary reference intakes (DRIs), changes in soil quality, and reductions in nutrient density are just a few of these factors. In this article, we propose a new, working approach towards human nutrition designated "Foundational Nutrition". This nutritional lens combines a whole food approach in conjunction with micronutrients and other nutrients critical for optimal human health with special consideration given to the human gut microbiome and overall gut health. Together, this a synergistic approach which addresses vital components in nutrition that enhances the bioavailability of nutrients and to potentiate a bioactive effect.


Subject(s)
Diet , Malnutrition , Humans , Nutritional Status , Recommended Dietary Allowances , Malnutrition/prevention & control , Nutrients , Micronutrients
2.
PeerJ ; 11: e14493, 2023.
Article in English | MEDLINE | ID: mdl-36620744

ABSTRACT

Background: Systematic reviews and meta-analyses related to high-intensity functional training (HIFT) have been conducted. However, due to a restricted pool of available research, these investigations are often limited in scope. As such, a scoping review investigating the present literature surrounding the acute physiological response to HIFT-based exercise was chosen as a more appropriate structured review. Methodology: A scoping review was conducted following Arksey and O'Malley's framework. Three large scale databases were searched to reveal any article pertaining to HIFT and related exercise terminology. Results: A total of 2,241 articles were found during the initial search. Following this, titles, then abstracts, and full-texts were reviewed to determine inclusion eligibility. A total of 60 articles which investigated a combined total of 35 unique HIFT workouts were included within this review. Conclusions: A variety of physiological parameters and HIFT workouts have been examined. Markers of intensity (e.g., blood lactate concentrations, heart rate) have been most consistently assessed across all studies, and these support the idea that HIFT workouts are typically performed at high-intensity. In contrast, the inclusion of most other measures (e.g., hormonal, markers of inflammation and damage, energy expenditure, performance) has been inconsistent and has thus, limited the possibility for making generalized conclusions. Differences in study methodologies have further impacted conclusions, as different studies have varied in sample population characteristics, workouts assessed, and time points. Though it may be impossible to comprehensively research all possible HIFT workouts, consistent adoption of population definitions and workload quantification may overcome this challenge and assist with future comparisons.


Subject(s)
High-Intensity Interval Training , Humans , Exercise , Inflammation
3.
Brain Behav Immun Health ; 20: 100415, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35112091

ABSTRACT

The purpose of this investigation was to compare changes in circulating lymphocyte subset cell counts between high-intensity interval exercise (HIIE), sprint interval exercise (SIE), and moderate-intensity continuous exercise (MICE). Recreationally active men (n â€‹= â€‹11; age: 23 â€‹± â€‹4 â€‹yr; height: 179.9 â€‹± â€‹4.5 â€‹cm; body mass: 79.8 â€‹± â€‹8.7 â€‹kg; body fat %:12.6 â€‹± â€‹3.8%; V̇O2max: 46.6 â€‹± â€‹3.9 â€‹ml⋅kg-1⋅min-1) completed a maximal graded exercise test to determine maximal oxygen uptake (V̇O2max) and three duration-matched cycling trials (HIIE, SIE, and MICE) in a randomized, counterbalanced fashion. HIIE consisted of fifteen 90-s bouts at 85% V̇O2max interspersed with 90-s active recovery periods. SIE consisted of fifteen 20-s bouts at 130% maximal power and 160-s active recovery periods. MICE was a continuous bout at 65% V̇O2max. Total exercise duration was 53 â€‹min in all three trials, including warm-up and cool-down. Blood was collected before, immediately post, 30 â€‹min, 2 â€‹h, 6 â€‹h, and 24 â€‹h post-exercise. Changes in lymphocyte subset counts, and surface expression of various markers were analyzed via flow cytometry. Changes were assessed using mixed model regression analysis with an autoregressive first order repeated measures correction. Significant decreases were observed in absolute counts of CD56dim NK cells, CD19+ B cells, CD4+ T cells, and CD8+ T cells 30 â€‹min and 24-h post-exercise in all three trials. Despite resulting in greater total work and oxygen consumption, MICE elicited similar changes in lymphocyte subset counts and receptor expression compared to both SIE and HIIE. Similarly, while the two interval trials resulted in differing oxygen consumption and total work, no differences in the lymphocyte response were observed. Though both forms of exercise resulted in declines in circulating lymphocyte cell counts, neither exercise type provides an immune-related advantage when matched for duration.

4.
Int J Exerc Sci ; 15(4): 45-57, 2022.
Article in English | MEDLINE | ID: mdl-36895846

ABSTRACT

This study sought to determine relationships between hexagonal barbell (HBB) deadlift one-repetition maximum (1-RM) and force-time characteristics of maximal isometric pulls. Twenty-three healthy adults (13 men [8 trained], 10 women [4 trained]) completed three visits consisting of a familiarization and anthropometrics session, a HBB deadlift 1-RM session, and a performance session with three maximal isometric pulls at three positions: lift-off (FLOOR), knee-passing (KNEE), and mid-thigh (MT). Correlation analyses assessed relationships between 1-RM and force-time characteristics at each position with significance set a priori at α ≤ 0.05. Correlation coefficients between 1-RM and force-time characteristics at all positions presented large to very large relationships to peak force (PF; r = 0.695-0.879, p ≤ 0.001), large to very large relationships to all time-specific force variables (r = 0.506-0.812; p ≤ 0.014), moderate to very large relationships between rate of force development (RFD) time-bands (r = 0.430-0.752; p ≤ 0.041), and large to very large relationships to impulse (r = 0.575-0.778; p ≤ 0.004). Collectively, more very large effect sizes (r = 0.7-0.89) were observed at FLOOR (n = 8) and KNEE (n = 6) than MT (n = 0). PF at FLOOR and KNEE presented as strongest predictors of maximal strength in the 1-RM HBB deadlift. The observed differences between positions may be due to exercise-specific disadvantageous positions commonly observed as isometric sticking points. Coaches should consider incorporating isometric pulls from the lift-off or knee passing positions as it appears to be better related to maximal strength than the isometric mid-thigh pull.

5.
Cytokine X ; 2(3): 100033, 2020 Sep.
Article in English | MEDLINE | ID: mdl-33604558

ABSTRACT

The purpose of this study was to evaluate the effects of aerobic exercise in the heat on circulating concentrations of tumor necrosis factor (TNF)-α, soluble TNF receptors (STNFR1&2), and surface expression of TNFR1&2 on monocyte subpopulations. Twelve recreationally active Caucasian men (24.4 ± 3.4 yrs.; 180.0 ± 6.8 cm; 81.5 ± 8.0 kg; 47.2 ± 4.8 mL·kg-1·min-1) completed an exercise protocol in three environmental conditions: high temperature/low humidity [HTLH; 35 °C, 20% relative humidity (RH)]; high temperature/moderate humidity (HTMH; 35 °C, 45%RH); and moderate temperature/moderate humidity (MTMH; 22 °C, 45%RH). Each protocol consisted of a 60-minute cycling trial at 60% VO2max, a 15-minute rest, and a time-to-exhaustion trial at 90% VO2max (TTE). Blood was sampled before (PRE), immediately after (POST) the 60-minute trial, immediately post-TTE (PTTE), and one-hour post-TTE (REC). Circulating TNF-α and STNFR1&2 were assayed. TNFR1&2 expression on monocyte subsets was measured by flow cytometry on a subset of participants (n = 8). TNF-α area under the curve with respect to increase (AUCi) was greater during HTMH compared to MTMH and HTLH. STNFR1 concentration was greater during HTMH compared to MTMH. With all trials combined, STNFR1 concentration increased from PRE to POST, PTTE, and REC. TNFR1 expression on non-classical monocytes was greater during HTMH compared to HTLH while TNFR2 expression was lower during HTLH compared to both MTMH and HTMH. Data suggest that exercise in the heat increases circulating TNF-α and STNFR1 concentration concomitantly. Furthermore, non-classical monocyte expression of TNFRs are impacted by temperature and humidity during exercise.

6.
J Strength Cond Res ; 32(11): 3160-3168, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30216251

ABSTRACT

Sell, KM, Prendergast, JM, Ghigiarelli, JJ, Gonzalez, AM, Biscardi, LM, Jajtner, AR, and Rothstein, AS. Comparison of physical fitness parameters for starters vs. nonstarters in an NCAA Division I men's lacrosse team. J Strength Cond Res 32(11): 3160-3168, 2018-The purpose of this study was to present a fitness profile of Division I male lacrosse players and compare the fitness attributes across different positions and starting status. Forty-one Division I men's lacrosse players (19.6 ± 1.6 years, 82.5 ± 9.5 kg, 182.0 ± 5.4 cm) volunteered to participate in the study. Fitness attributes assessed included aerobic fitness (1.5-mile run), muscular strength (1 repetition maximum bench press, squat, and hang clean), grip strength (hand dynamometer), explosive power (vertical jump), agility (3-cone drill, pro-agility), body composition (7-site skinfold), and speed (20- and 40-yard sprint). All testing was conducted by a certified strength and conditioning coach and occurred at the conclusion of pre-season training. The only significant difference across positions was for body mass, whereby defensemen were significantly heavier than attacking players (p < 0.05). Starters were significantly faster on the 3-cone drill, 20- and 40-yard sprint, and jumped significantly higher on the vertical jump compared with nonstarters (p < 0.05). Attributes pertaining to anaerobic fitness (speed, agility, and explosive power) may be better predictors of starting status than aerobic fitness in men's NCAA Division I lacrosse players. This differs from previous research on men's club lacrosse players where a difference in aerobic fitness and body composition was shown between starters and nonstarters. The normative data presented in this study may assist strength and conditioning coaches in the development of sport-specific training programs and motivate athletes toward achieving sport-specific fitness goals by helping identify areas of weakness before the start of the season.


Subject(s)
Athletic Performance , Physical Fitness , Racquet Sports , Athletes , Body Composition , Exercise Test , Humans , Male , Muscle Strength , Young Adult
7.
PLoS One ; 13(8): e0198304, 2018.
Article in English | MEDLINE | ID: mdl-30161137

ABSTRACT

Resistance training may differentially affect morphological adaptations along the length of uni-articular and bi-articular muscles. The purpose of this study was to compare changes in muscle morphology along the length of the rectus femoris (RF) and vastus lateralis (VL) in response to resistance training. Following a 2-wk preparatory phase, 15 resistance-trained men (24.0 ± 3.0 y, 90.0 ± 13.8 kg, 174.9 ± 20.7 cm) completed pre-training (PRE) assessments of muscle thickness (MT), pennation angle (PA), cross-sectional area (CSA), and echo-intensity in the RF and VL at 30, 50, and 70% of each muscle's length; fascicle length (FL) was estimated from respective measurements of MT and PA within each muscle and region. Participants then began a high intensity, low volume (4 x 3-5 repetitions, 3min rest) lower-body resistance training program, and repeated all PRE-assessments after 8 weeks (2 d ∙ wk-1) of training (POST). Although three-way (muscle [RF, VL] x region [30, 50, 70%] x time [PRE, POST]) repeated measures analysis of variance did not reveal significant interactions for any assessment of morphology, significant simple (muscle x time) effects were observed for CSA (p = 0.002) and FL (p = 0.016). Specifically, average CSA changes favored the VL (2.96 ± 0.69 cm2, p < 0.001) over the RF (0.59 ± 0.20 cm2, p = 0.011), while significant decreases in average FL were noted for the RF (-1.03 ± 0.30 cm, p = 0.004) but not the VL (-0.05 ± 0.36 cm, p = 0.901). No other significant differences were observed. The findings of this study demonstrate the occurrence of non-homogenous adaptations in RF and VL muscle size and architecture following 8 weeks of high-intensity resistance training in resistance-trained men. However, training does not appear to influence region-specific adaptations in either muscle.


Subject(s)
Adaptation, Physiological/physiology , Muscle Strength/physiology , Quadriceps Muscle/physiology , Resistance Training , Adult , Exercise/physiology , Humans , Male , Muscle, Skeletal/physiology , Quadriceps Muscle/anatomy & histology , Young Adult
8.
Med Sci Sports Exerc ; 50(11): 2231-2241, 2018 11.
Article in English | MEDLINE | ID: mdl-29957728

ABSTRACT

PURPOSE: To examine the impact of polyphenol supplementation on the recruitment, mobilization, and activation of monocyte subsets after resistance exercise. METHODS: Thirty-eight recreationally active males (22.1 ± 3.1 yr; 173.9 ± 7.9 cm; 77.8 ± 14.5 kg) were assigned to 28 d of polyphenol blend (PPB) supplementation, placebo (PL), or control (CON). Blood samples were obtained before (PRE) postresistance exercise, immediately (IP) postresistance exercise, 1 h (1H) postresistance exercise, 5 h (5H) postresistance exercise, 24 h (24H) postresistance exercise, and 48 h (48H) postresistance exercise (PPB/PL) or rest (CON). Fine-needle biopsies were obtained from the vastus lateralis at PRE, 1H, 5H, and 48H. Circulating concentrations of macrophage chemoattractant protein-1 (MCP-1) and fractalkine, as well as intramuscular MCP-1 were analyzed via multiplex assay. Changes in the proportions and expression of CD11b on monocyte subsets were assessed via flow cytometry. RESULTS: Circulating MCP-1 increased in PPB and PL at IP with further increases at 5H. Intramuscular MCP-1 was increased at 1H, 5H, and 48H in all groups. Classical monocyte proportions were reduced in PPB and PL at IP, and increased at 1H. Nonclassical monocytes were increased in PPB and PL at IP, whereas intermediate monocytes were increased at IP, and reduced at 1H. Intermediate monocytes were increased in PPB at 24H and 48H. CD11b expression was reduced on PPB compared with PL and CON at PRE on intermediate and nonclassical monocytes. CONCLUSIONS: Resistance exercise may elicit selective mobilization of intermediate monocytes at 24H and 48H, which may be mediated by tissue damage. Additionally, polyphenol supplementation may suppress CD11b expression on monocyte subsets at rest.


Subject(s)
Antioxidants/administration & dosage , Dietary Supplements , Monocytes/metabolism , Polyphenols/administration & dosage , Quadriceps Muscle/metabolism , Resistance Training , CD11b Antigen/blood , Chemokine CCL2/blood , Chemokine CCL2/metabolism , Chemokine CX3CL1/blood , Humans , Macrophage-1 Antigen/blood , Male , Time Factors , Young Adult
9.
Physiol Rep ; 6(2)2018 01.
Article in English | MEDLINE | ID: mdl-29380956

ABSTRACT

The purpose of this study was to examine the effects of 28-days of supplementation with an aqueous proprietary polyphenol blend (PPB) sourced from Camellia sinensis on intramuscular apoptotic signaling following an acute lower-body resistance exercise protocol and subsequent recovery. Untrained males (n = 38, 21.8 ± 2.7 years, 173.4 ± 7.9 cm, 77.6 ± 14.6 kg) were randomized to PPB (n = 14), placebo (PL; n = 14) or control (CON; n = 10). Participants completed a lower-body resistance exercise protocol comprised of the squat, leg press, and leg extension exercises. Skeletal muscle microbiopsies were obtained from the vastus lateralis preexercise (PRE), 1-h (1HR), 5-h (5HR), and 48-h (48HR) post-resistance exercise. Apoptotic signaling pathways were quantified using multiplex signaling assay kits to quantify total proteins (Caspase 3, 8, 9) and markers of phosphorylation status (JNK, FADD, p53, BAD, Bcl-2). Changes in markers of muscle damage and intramuscular signaling were analyzed via separate repeated measures analysis of variance (ANOVA). Change in Bcl-2 phosphorylation at 1H was significantly greater in PL compared to CON (P = 0.001). BAD phosphorylation was significantly elevated at 5H in PL compared to PPB (P = 0.015) and CON (P = 0.006). The change in JNK phosphorylation was significantly greater in PPB (P = 0.009), and PL (P = 0.017) compared to CON at 1H, while the change for PL was elevated compared to CON at 5H (P = 0.002). A main effect was observed (P < 0.05) at 1H, 5H, and 48H for p53 and Caspase 8, with Caspase 3 and Caspase 9 elevated at 48H. These data indicate that chronic supplementation with PPB alters apoptotic signaling in skeletal muscle following acute muscle-damaging resistance exercise.


Subject(s)
Dietary Supplements , Muscle, Skeletal/physiology , Plant Extracts/pharmacology , Polyphenols/pharmacology , Resistance Training , Apoptosis/physiology , Humans , Male , Young Adult
10.
J Strength Cond Res ; 31(11): 2945-2954, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29068862

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. 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.


Subject(s)
Muscle Strength/drug effects , Muscle, Skeletal/drug effects , Polyphenols/therapeutic use , Resistance Training/methods , Adolescent , Adult , Double-Blind Method , Exercise Test , Humans , Male , Young Adult
11.
Amino Acids ; 49(8): 1415-1426, 2017 08.
Article in English | MEDLINE | ID: mdl-28555251

ABSTRACT

Attenuating TNFα/TNFr1 signaling in monocytes has been proposed as a means of mitigating inflammation. The purpose of this study was to examine the effects of a milk protein supplement on TNFα and monocyte TNFr1 expression. Ten resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) ingested supplement (SUPP) or placebo (PL) immediately post-exercise in a randomized, cross-over design. Blood samples were obtained at baseline (BL), immediately (IP), 30-min (30P), 1-h (1H), 2-h (2H), and 5-h (5H) post-exercise to assess plasma concentrations of myoglobin; tumor necrosis factor-alpha (TNFα); and expression of tumor necrosis factor receptor 1 (TNFr1) on classical, intermediate, and non-classical monocytes. Magnitude-based inferences were used to provide inferences on the true effects of SUPP compared to PL. Plasma TNFα concentrations were "likely attenuated" (91.6% likelihood effect) from BL to 30P in the SUPP group compared with PL (d = 0.87; mean effect: 2.3 ± 2.4 pg mL-1). TNFr1 expressions on classical (75.9% likelihood effect) and intermediate (93.0% likelihood effect) monocytes were "likely attenuated" from BL to 2H in the SUPP group compared with PL (d = 0.67; mean effect: 510 ± 670 RFU, and d = 1.05; mean effect: 2500 ± 2300 RFU, respectively). TNFr1 expression on non-classical monocytes was "likely attenuated" (77.6% likelihood effect) from BL to 1H in the SUPP group compared with PL (d = 0.69; mean effect: 330 ± 430 RFU). Ingestion of a milk protein supplement immediately post-exercise appears to attenuate both plasma TNFα concentrations and TNFr1 expression on monocyte subpopulations in resistance-trained men.


Subject(s)
Dietary Supplements , Milk Proteins/administration & dosage , Monocytes/metabolism , Receptors, Tumor Necrosis Factor, Type I/blood , Resistance Training , Tumor Necrosis Factor-alpha/blood , Adult , Cells, Cultured , Cross-Over Studies , Eating , Humans , Inflammation/metabolism , Inflammation/prevention & control , Male , Monocytes/cytology , Young Adult
12.
J Strength Cond Res ; 31(1): 45-53, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28005636

ABSTRACT

Mangine, GT, Hoffman, JR, Gonzalez, AM, Townsend, JR, Wells, AJ, Jajtner, AR, Beyer, KS, Boone, CH, Wang, R, Miramonti, AA, LaMonica, MB, Fukuda, DH, Witta, EL, Ratamess, NA, and Stout, JR. Exercise-induced hormone elevations are related to muscle growth. J Strength Cond Res 31(1): 45-53, 2017-Partial least squares regression structural equation modeling (PLS-SEM) was used to examine relationships between the endocrine response to resistance exercise and muscle hypertrophy in resistance-trained men. Pretesting (PRE) measures of muscle size (thickness and cross-sectional area) of the vastus lateralis and rectus femoris were collected in 26 resistance-trained men. Participants were randomly selected to complete a high-volume (VOL, n = 13, 10-12RM, 1-minute rest) or high-intensity (INT, n = 13, 3-5RM, 3-minute rest) resistance training program. Blood samples were collected at baseline, immediately postexercise, 30-minute, and 60-minute postexercise during weeks 1 (week 1) and 8 (week 8) of training. The hormonal responses (testosterone, growth hormone [22 kD], insulin-like growth factor-1, cortisol, and insulin) to each training session were evaluated using area-under-the-curve (AUC) analyses. Relationships between muscle size (PRE), AUC values (week 1 + week 8) for each hormone, and muscle size (POST) were assessed using a consistent PLS-SEM algorithm and tested for statistical significance (p ≤ 0.05) using a 1,000 samples consistent bootstrapping analysis. Group-wise comparisons for each relationship were assessed through independent t-tests. The model explained 73.4% (p < 0.001) of variance in muscle size at POST. Significant pathways between testosterone and muscle size at PRE (p = 0.043) and muscle size at POST (p = 0.032) were observed. The ability to explain muscle size at POST improved when the model was analyzed by group (INT: R = 0.882; VOL: R = 0.987; p < 0.001). No group differences in modal quality were found. Exercise-induced testosterone elevations, independent of the training programs used in this study, seem to be related to muscle growth.


Subject(s)
Muscle, Skeletal/physiology , Resistance Training/methods , Adult , Athletes , Human Growth Hormone/blood , Humans , Hydrocortisone/blood , Insulin-Like Growth Factor I/biosynthesis , Male , Muscle, Skeletal/blood supply , Quadriceps Muscle/physiology , Rest/physiology , Testosterone/blood , Young Adult
13.
Eur J Appl Physiol ; 116(11-12): 2367-2374, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27744584

ABSTRACT

PURPOSE: To compare the effects of two different resistance training programs, high intensity (INT) and high volume (VOL), on changes in isometric force (FRC), rate of force development (RFD), and barbell velocity during dynamic strength testing. METHODS: Twenty-nine resistance-trained men were randomly assigned to either the INT (n = 15, 3-5 RM, 3-min rest interval) or VOL (n = 14, 10-12 RM, 1-min rest interval) training group for 8 weeks. All participants completed a 2-week preparatory phase prior to randomization. Measures of barbell velocity, FRC, and RFD were performed before (PRE) and following (POST) the 8-week training program. Barbell velocity was determined during one-repetition maximum (1RM) testing of the squat (SQ) and bench press (BP) exercises. The isometric mid-thigh pull was used to assess FRC and RFD at specific time bands ranging from 0 to 30, 50, 90, 100, 150, 200, and 250 ms. RESULTS: Analysis of covariance revealed significant (p < 0.05) group differences in peak FRC, FRC at 30-200 ms, and RFD at 50-90 ms. Significant (p < 0.05) changes in INT but not VOL in peak FRC (INT: 9.2 ± 13.8 %; VOL: -4.3 ± 10.2 %), FRC at 30-200 ms (INT: 12.5-15.8 %; VOL: -1.0 to -4.3 %), and RFD at 50 ms (INT: 78.0 ± 163 %; VOL: -4.1 ± 49.6 %) were observed. A trend (p = 0.052) was observed for RFD at 90 ms (INT: 58.5 ± 115 %; VOL: -3.5 ± 40.1 %). No group differences were observed for the observed changes in barbell velocity. CONCLUSIONS: Results indicate that INT is more advantageous than VOL for improving FRC and RFD, while changes in barbell velocity during dynamic strength testing are similarly improved by both protocols in resistance-trained men.


Subject(s)
High-Intensity Interval Training/methods , Isometric Contraction/physiology , Muscle Strength/physiology , Muscle, Skeletal/physiology , Physical Exertion/physiology , Resistance Training/methods , Female , Humans , Male , Physical Fitness/physiology , Young Adult
14.
Eur J Appl Physiol ; 116(11-12): 2103-2111, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27582262

ABSTRACT

PURPOSE: The NF-κB signaling pathway regulates multiple cellular processes following exercise stress. This study aims to examine the effects of an acute lower-body resistance exercise protocol and subsequent recovery on intramuscular NF-κB signaling. METHODS: Twenty-eight untrained males were assigned to either a control (CON; n = 11) or exercise group (EX; n = 17) and completed a lower-body resistance exercise protocol consisting of the back squat, leg press, and leg extension exercises. Skeletal muscle microbiopsies were obtained from the vastus lateralis pre-exercise (PRE), 1-hour (1H), 5-hours (5H), and 48-hours (48H) post-resistance exercise. Multiplex signaling assay kits (EMD Millipore, Billerica, MA, USA) were used to quantify the total protein (TNFR1, c-Myc) or phosphorylation status of proteins belonging to the NF-κB signaling pathway (IKKa/b, IkBα, NF-κB) using multiplex protein assay. Repeated measures ANOVA analysis was used to determine the effects of the exercise bout on intramuscular signaling at each time point. Additionally, change scores were analyzed by magnitude based inferences to determine a mechanistic interpretation. RESULTS: Repeated measures ANOVA indicated a trend for a two-way interaction between the EX and CON Group (p = 0.064) for c-Myc post resistance exercise. Magnitude based inference analysis suggest a "Very Likely" increase in total c-Myc from PRE-5H and a "Likely" increase in IkBα phosphorylation from PRE-5H post-resistance exercise. CONCLUSION: Results indicated that c-Myc transcription factor is elevated following acute intense resistance exercise in untrained males. Future studies should examine the role that post-resistance exercise NF-κß signaling plays in c-Myc induction, ribosome biogenesis and skeletal muscle regeneration.


Subject(s)
Muscle Contraction/physiology , Muscle, Skeletal/physiology , NF-kappa B/metabolism , Physical Conditioning, Human/methods , Resistance Training/methods , Humans , Male , Sedentary Behavior , Signal Transduction/physiology , Stress, Physiological/physiology , Young Adult
15.
Nutrients ; 8(7)2016 Jul 02.
Article in English | MEDLINE | ID: mdl-27384580

ABSTRACT

The recruitment and infiltration of classical monocytes into damaged muscle is critical for optimal tissue remodeling. This study examined the effects of an amino acid supplement on classical monocyte recruitment following an acute bout of lower body resistance exercise. Ten resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) ingested supplement (SUPP) or placebo (PL) immediately post-exercise in a randomized, cross-over design. Blood samples were obtained at baseline (BL), immediately (IP), 30-min (30P), 1-h (1H), 2-h (2H), and 5-h (5H) post-exercise to assess plasma concentrations of monocyte chemoattractant protein 1 (MCP-1), myoglobin, cortisol and insulin concentrations; and expressions of C-C chemokine receptor-2 (CCR2), and macrophage-1 antigen (CD11b) on classical monocytes. Magnitude-based inferences were used to provide inferences on the true effects of SUPP compared to PL. Changes in myoglobin, cortisol, and insulin concentrations were similar between treatments. Compared to PL, plasma MCP-1 was "very likely greater" (98.1% likelihood effect) in SUPP at 2H. CCR2 expression was "likely greater" at IP (84.9% likelihood effect), "likely greater" at 1H (87.7% likelihood effect), "very likely greater" at 2H (97.0% likelihood effect), and "likely greater" at 5H (90.1% likelihood effect) in SUPP, compared to PL. Ingestion of SUPP did not influence CD11b expression. Ingestion of an amino acid supplement immediately post-exercise appears to help maintain plasma MCP-1 concentrations and augment CCR2 expression in resistance trained men.


Subject(s)
Amino Acids/administration & dosage , Chemokine CCL2/blood , Dietary Supplements , Receptors, CCR2/metabolism , Resistance Training , Administration, Oral , Adult , Biomarkers/blood , Body Mass Index , Body Weight , CD11b Antigen/genetics , CD11b Antigen/metabolism , Cross-Over Studies , Diet , Humans , Hydrocortisone/blood , Insulin/blood , Lactic Acid/blood , Male , Monocytes/drug effects , Myoglobin/blood , Receptors, CCR2/genetics , Young Adult
16.
J Strength Cond Res ; 30(7): 1917-23, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27331915

ABSTRACT

Boone, CH, Hoffman, JR, Gonzalez, AM, Jajtner, AR, Townsend, JR, Baker, KM, Fukuda, DH, and Stout, JR. Changes in plasma aldosterone and electrolytes following high-volume and high-intensity resistance exercise protocols in trained men. J Strength Cond Res 30(7): 1917-1923, 2016-Program variables such as training intensity, volume, and rest interval length are known to elicit distinct hormonal, metabolic, and physical responses. However, little is known regarding resistance exercise (RE) program design and the fluid regulatory response. This investigation aimed to compare the plasma aldosterone (ALD), electrolyte, plasma volume (PV), and osmolality (Posm) responses following high-volume (HV; 4-6 × 10-12 reps, 70% 1 repetition maximum [1RM], 60-s rest) and high-intensity (HI; 6 × 3-5 reps, 90% 1RM, 180-second rest) RE protocols. Ten experienced, resistance-trained men (24.7 ± 3.4 years; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) performed each protocol in a random, counterbalanced order. Blood samples were obtained at baseline (BL), immediately (IP), 30 minutes (30P), and 1 hour (1H) postexercise. Significant trial × time interactions (p < 0.01) were observed in Posm, sodium (Na), and potassium (K), whereas a trend (p = 0.06) was observed for ALD. The PV shift from BL-30P was greater than BL-IP and BL-1H (p ≤ 0.05), but no significant between-trial differences were noted. Comparisons between RE protocols revealed significantly greater (p ≤ 0.05) elevations during HV vs. HI in Posm at IP, 30P, and 1H; and Na at IP and 30P. During HV, significant reductions (p ≤ 0.05) were noted in K at IP compared with HI. Area under the curve analysis indicates a trend (p = 0.07) toward a higher ALD response following HV compared with HI. Results of this study indicate that high-volume, moderate-intensity resistance exercise seems to augment the fluid regulatory response to a greater extent than low-volume, high-intensity training.


Subject(s)
Aldosterone/blood , Electrolytes/blood , Resistance Training/methods , Adult , Humans , Male , Osmolar Concentration , Plasma Volume , Random Allocation , Rest/physiology , Young Adult
17.
Eur J Appl Physiol ; 116(9): 1663-70, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27333913

ABSTRACT

PURPOSE: To examine the mitogen-activated protein kinase (MAPK) family of signaling proteins following typical high volume (HV) and high intensity (HI) lower body resistance exercise protocols in resistance-trained men. METHODS: Ten resistance-trained men (24.7 ± 3.4 year; 90.1 ± 11.3 kg; 176.0 ± 4.9 cm) performed each resistance exercise protocol in a random, counterbalanced order. The HV protocol utilized a load of 70 % 1-RM for sets of 10-12 repetitions with a 1-min rest period length between sets and exercises. The HI protocol utilized a load of 90 % 1-RM for sets of 3-5 repetitions with a 3-min rest period length between sets and exercises. Both protocols included six sets of barbell back squats and four sets of bilateral leg press, bilateral hamstring curls, bilateral leg extensions, and seated calf raises. Fine needle muscle biopsies of the vastus lateralis were completed at baseline (BL) and 1-h post exercise (1H). RESULTS: No significant differences over time were noted for phosphorylation of MEK1, ERK1/2, p38, MSK1, ATF2, p53, or c-Jun (p > 0.05). No significance between trial interactions was noted for phosphorylation of MAPK signaling proteins, including MEK1, ERK1/2, p38, JNK, MSK1, ATF2, STAT1, p53, c-Jun, or HSP27 (p > 0.05). However, significant time effects were observed for phosphorylation of JNK (p < 0.01), HSP27 (p < 0.01), and STAT1 (p = 0.03). Phosphorylation of JNK, HSP27, and STAT1 was significantly elevated from BL at 1H for both HV and HI. CONCLUSIONS: HV and HI lower body resistance exercise protocols appear to elicit similar MAPK activation in resistance-trained men.


Subject(s)
High-Intensity Interval Training/methods , MAP Kinase Signaling System/physiology , Mitogen-Activated Protein Kinase Kinases/metabolism , Muscle, Skeletal/physiology , Physical Conditioning, Human/physiology , Resistance Training/methods , Exercise/physiology , Humans , Leg/physiology , Male , Physical Conditioning, Human/methods , Physical Exertion/physiology , Physical Fitness/physiology , Young Adult
18.
Nutr Res ; 36(6): 553-63, 2016 06.
Article in English | MEDLINE | ID: mdl-27188901

ABSTRACT

This study tested the hypothesis that of 23 days of ß-hydroxy-ß-methylbutyrate (HMB) supplementation can maintain muscle mass and attenuate the immune and inflammatory response in combat soldiers during highly intense military training. Soldiers were randomly assigned to either a HMB (n = 6) or placebo (PL; n = 7) group and provided with 3 g · day(-1) of either HMB or PL. During the final week of supplementation soldiers participated in extreme physical training, which included night navigation of 6-8 hours across difficult terrain carrying heavy loads combined with sleep deprivation (3.8 ± 3.0 h per night). Blood draws were performed prior to and following the supplementation period. Magnetic resonance imaging, which included diffusion tensor imaging sequence, was used for muscle fiber tracking analysis. Data was analyzed using a two-way mixed factorial analysis of variance. Magnitude-based inferences were used to provide inferences on the true effects that HMB may have had on the dependent variables compared to PL, calculated from 90% confidence intervals. Changes in tumor necrosis factor-α for HMB (-3.9 ± 8.2 pg · mL(-1)) were significantly lower (P = .043) compared to the change in PL (+4.0 ± 3.7 pg · mL(-1)). HMB ingestion was also very likely (92%-95% Likelihood) to lower granulocyte colony-stimulating factor and interleukin 10 compared to PL. In addition, HMB supplementation was likely (78%-87% likelihood) to reduce interferon-γ, interleukin 8, CX3CL1, and increase muscle volume for the adductor magnus (77% likelihood) compared to PL. In summary, the results of this study provides evidence that HMB supplementation may attenuate the inflammatory response to high intense military training, and maintain muscle quality.


Subject(s)
Cytokines/blood , Dietary Supplements , Exercise , Military Personnel , Valerates/administration & dosage , Chemokine CX3CL1/metabolism , Creatine Kinase/blood , Diffusion Tensor Imaging , Double-Blind Method , Humans , L-Lactate Dehydrogenase/blood , Magnetic Resonance Imaging , Male , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Patient Compliance , Physical Endurance/drug effects
19.
J Appl Physiol (1985) ; 121(1): 123-8, 2016 07 01.
Article in English | MEDLINE | ID: mdl-27231312

ABSTRACT

This study compared the acute and chronic response of circulating plasma brain-derived neurotrophic factor (BDNF) to high-intensity low-volume (HI) and low-intensity high volume (HV) resistance training. Twenty experienced resistance-trained men (23.5 ± 2.6 y, 1.79 ± 0.05 m, 75.7 ± 13.8 kg) volunteered for this study. Before the resistance training program (PRE), participants performed an acute bout of exercise using either the HI [3-5 reps; 90% of one repetition maximum (1RM)] or HV (10-12 reps; 70% 1RM) training paradigm. The acute exercise protocol was repeated after 7 wk of training (POST). Blood samples were obtained at rest (BL), immediately (IP), 30 min (30P), and 60 min (60P) post exercise at PRE and POST. A three-way repeated measure ANOVA was used to analyze acute changes in BDNF concentrations during HI and HV resistance exercise and the effect of 7 wk of training. No training × time × group interaction in BDNF was noted (P = 0.994). Significant main effects for training (P = 0.050) and time (P < 0.001) in BDNF were observed. Significant elevations in BDNF concentrations were seen from BL at IP (P = 0.001), 30P (P < 0.001), and 60P (P < 0.001) in both HI and HV combined during PRE and POST. BDNF concentrations were also observed to increase from PRE to POST when collapsed across groups and time. No significant group × training interaction (P = 0.342), training (P = 0.105), or group (P = 0.238) effect were noted in the BDNF area under the curve response. Results indicate that BDNF concentrations are increased after an acute bout of resistance exercise, regardless of training paradigm, and are further increased during a 7-wk training program in experienced lifters.


Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Exercise/physiology , Aged , Humans , Male , Resistance Training/methods , Rest/physiology
20.
Med Sci Sports Exerc ; 48(6): 1169-78, 2016 06.
Article in English | MEDLINE | ID: mdl-26784277

ABSTRACT

UNLABELLED: The innate immune response is generally considered to have an important role in tissue remodeling after resistance exercise. PURPOSE: The purpose of this study was to compare changes in markers of monocyte recruitment after an acute bout of high-intensity (HVY) versus high-volume (VOL) lower-body resistance exercise. METHODS: Ten resistance-trained men (24.7 ± 3.4 yr, 90.1 ± 11.3 kg, 176.0 ± 4.9 cm) performed each protocol in a randomized, counterbalanced order. Blood samples were collected at baseline, immediately (IP), 30 min (30P), 1 h (1H), 2 h (2H), and 5 h (5H) postexercise. Plasma concentrations of monocyte chemoattractant protein 1 (MCP-1), tumor necrosis factor alpha (TNF-α), myoglobin, and cortisol were measured via assay. Tumor necrosis factor receptor 1 (TNFr1), macrophage-1 antigen (cluster of differentiation 11b [CD11b]), and C-C chemokine receptor 2 (CCR2) expression levels were measured using flow cytometry. TNFr1 and CD11b were assessed on CD14CD16 monocytes, whereas CCR2 was assessed on CD14 monocytes. RESULTS: Plasma myoglobin concentrations were significantly greater after HVY compared with VOL (P < 0.001). Changes in plasma TNF-α, MCP-1, and expression levels of CCR2 and CD11b were similar between HVY and VOL. When collapsed across groups, TNF-α was significantly increased at IP, 30P, 1H, and 2H (P values < 0.05), whereas MCP-1 was significantly elevated at all postexercise time points (P values < 0.05). CCR2 expression on CD14 monocytes was significantly lower at IP, 1H, 2H, and 5H (P values < 0.05). CD11b expression on CD14 CD16 was significantly greater at IP (P < 0.014) and 1H (P = 0.009). TNFr1 expression did not differ from baseline at any time point. Plasma cortisol concentrations did not seem to be related to receptor expression. CONCLUSIONS: Results indicate that both HVY and VOL protocols stimulate a robust proinflammatory response. However, no differences were noted between resistance exercise training paradigms.


Subject(s)
Monocytes/metabolism , Resistance Training/methods , CD11b Antigen/blood , Chemokine CCL2/blood , Humans , Hydrocortisone/blood , Immunity, Innate/physiology , Macrophage-1 Antigen/blood , Male , Myoglobin/blood , Receptors, CCR2/blood , Receptors, Tumor Necrosis Factor, Type I/blood , Tumor Necrosis Factor-alpha/blood , Young Adult
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