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1.
J Funct Morphol Kinesiol ; 6(4)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34842757

RESUMO

PURPOSE: The purpose of this study was to determine whether session rating of perceived exertion-derived training load (sRPE-TL) correlates with GPS-derived measures of external load in National Collegiate Athletics Association (NCAA) Division I female soccer athletes. METHODS: Twenty-one NCAA Division 1 collegiate women's soccer athletes (11 starters, 10 non-starters; 65.1 ± 7.2 kg, 168.4 ± 7.9 cm, 20.3 ± 1.5 yrs) volunteered to take part in this study. Data for this study were collected over the course of 16 weeks during the 2018 NCAA women's soccer season. External load and heart rate (HR) data were collected during each training session and match during the season. At least 30 min after the end of an activity (e.g., match or practice), athletes were prompted to complete a questionnaire reporting their perceived exertion for the session. sRPE-TL was calculated at the end of the season by multiplying perceived exertion by the respective session duration. RESULTS: sRPE-TL was very strongly correlated with total distance, distance covered in velocity zones 1-3, the number of accelerations in zones 4 and 5, total PlayerLoad™, and PlayerLoad™. For internal load, sRPE-TL correlated very strongly (0.70 ≤ |r| < 0.90) with Edward's and Bannister's TRIMP and strongly (0.50 ≤ |r| < 0.70) with duration spent in in heart rate zones 5 and 6 (80-90% and 90-100% max HR, respectively) while correlations with maximum HR (bpm), mean HR (bpm), and mean HR (%) and sRPE-TL were moderate (0.30 ≤ |r| < 0.50). CONCLUSIONS: In NCAA Division I women soccer, sRPE-TL is strongly associated with external measures of workload. These relationships were stronger during match play, with acceleration load and total distance exhibiting the strongest relationship with sRPE-TL.

2.
Nutrients ; 13(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34836033

RESUMO

BACKGROUND: EPA and DHA n-3 FA play crucial roles in both neurological and cardiovascular health and high dietary intakes along with supplementation suggest potential neuroprotection and concussion recovery support. Rugby athletes have a high risk of repetitive sub-concussive head impacts which may lead to long-term neurological deficits, but there is a lack of research looking into n-3 FA status in rugby players. We examined the dietary n-3 FA intake through a FFQ and n-3 FA status by measuring the percentage of n-3 FA and O3I in elite Canadian Rugby 7s players to show distribution across O3I risk zones; high risk, <4%; intermediate risk, 4 to 8%; and low risk, >8%. METHODS: n-3 FA profile and dietary intake as per FFQ were collected at the beginning of the 2017-2018 Rugby 7s season in male (n = 19; 24.84 ± 2.32 years; 95.23 ± 6.93 kg) and female (n = 15; 23.45 ± 3.10 years; 71.21 ± 5.79 kg) athletes. RESULTS: O3I averaged 4.54% ± 1.77, with female athlete scores slightly higher, and higher O3I scores in supplemented athletes (4.82% vs. 3.94%, p = 0.183), with a greater proportion of non-supplemented athletes in the high-risk category (45.5% vs. 39.1%). Dietary intake in non-supplemented athletes did not meet daily dietary recommendations for ALA or EPA + DHA compared to supplemented athletes. CONCLUSIONS: Overall, despite supplementation, O3I score remained in the high-risk category in a proportion of athletes who met recommended n-3 FA dietary intakes, and non-supplemented athletes had a higher proportion of O3I scores in the high-risk category, suggesting that dietary intake alone may not be enough and athletes may require additional dietary and n-3 FA supplementation to reduce neurological and cardiovascular risk.

3.
J Int Soc Sports Nutr ; 18(1): 65, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34579748

RESUMO

BACKGROUND: American-style football (ASF) athletes are at risk for cardiovascular disease (CVD) and exhibit elevated levels of serum neurofilament light (Nf-L), a biomarker of axonal injury that is associated with repetitive head impact exposure over the course of a season of competition. Supplementation with the w-3 fatty acid (FA) docosahexaenoic acid (DHA) attenuates serum Nf-L elevations and improves aspects of CVD, such as the omega-3 index (O3I). However, the effect of combining the w-3 FA eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA) with DHA on, specifically, serum Nf-L in ASF athletes is unknown. Therefore, this study assessed the effect of supplemental w-3 FA (EPA+DPA+DHA) on serum Nf-L, plasma w-3 FAs, the O3I, and surrogate markers of inflammation over the course of a season. METHODS: A multi-site, non-randomized design, utilizing two American football teams was employed. One team (n = 3 1) received supplementation with a highly bioavailablew-3 FA formulation (2000mg DHA, 560mg EPA, 320mg DPA, Mindset®, Struct Nutrition, Missoula, MT) during pre-season and throughout the regular season, while the second team served as the control (n = 35) and did not undergo supplementation. Blood was sampled at specific times throughout pre- and regular season coincident w ith changes in intensity, physical contact, and changes in the incidence and severity of head impacts. Group differences were determined via a mixed-model between-within subjects ANOVA. Effect sizes were calculated using Cohen's dfor all between-group differences. Significance was set a priori at p< .05. RESULTS: Compared to the control group, ASF athletes in the treatment group experienced large increases in plasma EPA (p < .001, d = 1.71) and DHA (p < .001, d = 2.10) which contributed to increases in the O3I (p < .001, d = 2.16) and the EPA:AA ratio (p = .001, d = 0.83) and a reduction in the w-6: w-3 ratio (p < .001, d = 1.80). w-3 FA supplementation attenuated elevations in Nf-L (p = .024). The control group experienced a significant increase in Nf-L compared to baseline at several measurement time points (T2, T3, and T4 [p range < .001 - .005, drange = 0.59-0.85]). CONCLUSIONS: These findings suggest a cardio- and neuroprotective effect of combined EPA+DPA+DHA w-3 FA supplementation in American-style football athletes. TRIAL REGISTRATION: This trial was registered with the ISRCTN registry ( ISRCTN90306741 ).


Assuntos
Traumatismos em Atletas/sangue , Traumatismos Craniocerebrais/sangue , Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Futebol Americano/lesões , Atletas , Biomarcadores/sangue , Ácidos Docosa-Hexaenoicos/sangue , Ácido Eicosapentaenoico/sangue , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Insaturados/sangue , Humanos , Masculino
4.
Clin J Sport Med ; 31(3): 250-256, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30839351

RESUMO

OBJECTIVE: To examine changes in blood biomarkers, serum neurofilament light (Nf-L), and plasma tau, as well as the relationship between blood biomarkers and symptom reports, in athletes with a sports-related concussion. DESIGN: Prospective cohort study. SETTING: Private community-based concussion clinic. PARTICIPANTS: Athletes aged 13 to 18 years old with a diagnosed sports-related concussion presenting to a concussion clinic within 7 days of injury and noninjured athletes with no history of concussion aged 13 to 23 years old. ASSESSMENT AND MAIN OUTCOME MEASURES: Injured athletes provided a blood sample at the initial clinical evaluation and again at least 6 months after injury. Noninjured athletes provided a single blood sample. All participants completed symptom reports during each visit. Statistical comparisons of biomarker concentrations and symptom reports were conducted. RESULTS: The mean rank for tau was significantly lower for concussed athletes compared with nonconcussed athletes. In contrast, the mean rank of Nf-L was higher for concussed athletes than for nonconcussed athletes, although the difference was nonsignificant. Plasma tau was significantly lower postinjury compared with 6 months after injury, whereas serum Nf-L was significantly higher postinjury. There was a weak but significant inverse relationship observed between tau and the number of symptoms reported, but no relationship was observed between Nf-L and the number of symptoms reported. CONCLUSIONS: These data indicate that in the days following a sports-related concussion, the blood biomarkers tau and Nf-L display contrasting patterns of change but may not be related to self-reported symptom scores.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Adolescente , Atletas , Traumatismos em Atletas/diagnóstico , Biomarcadores/sangue , Concussão Encefálica/diagnóstico , Humanos , Testes Neuropsicológicos , Estudos Prospectivos , Esportes , Adulto Jovem
5.
J Strength Cond Res ; 34(11): 3055-3061, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33105354

RESUMO

Bisch, KL, Bosch, TA, Carbuhn, A, Stanforth, PR, Oliver, JM, Bach, CW, and Dengel, DR. Positional body composition of female division I collegiate volleyball players. J Strength Cond Res 34(11): 3055-3061, 2020-The primary study objective was to measure positional differences in total and regional body composition among female NCAA Division I collegiate volleyball players using dual X-ray absorptiometry (DXA). The secondary objective was to examine normative age curves for fat and lean mass (LM) variables. Ninety female volleyball players from 5 universities received a DXA scan. Athletes were categorized by position: middle blocker (MB = 31), outside hitter (OH = 32), setter (ST = 9), and Libero (LB = 18). Height, body mass, total and regional fat mass (FM), LM, bone mineral density (BMD), and abdominal visceral adipose tissue were measured by DXA. Body mass distribution ratios were calculated. The secondary age analysis included a subset of 153 DXA scans (n = 83, ages 18-21 years). Front row players (i.e., MB and OH) had significantly greater total and regional LM and BMD measures (p < 0.05, all), compared with non-front row players (i.e., LB and ST). Differences in total LM (p < 0.001) were significantly influenced by height. Front row players had consistently lower mass distribution ratios compared with non-front row players (p < 0.05, all). Lean mass index (LMI, p = 0.752) and FM index (FMI, p = 0.392) were not significantly different across ages. Back row players have greater relative upper body mass, whereas mass in front row players is more evenly distributed between the upper and lower body. Bone mineral density differences may be influenced by repeated impact of jumping during the attacking and blocking actions of front row players. Minimal changes in LMI and fluctuations in FMI can be expected across an athlete's career.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Voleibol/fisiologia , Absorciometria de Fóton , Adolescente , Atletas , Feminino , Humanos , Gordura Intra-Abdominal/fisiologia , Estudos Retrospectivos , Universidades , Adulto Jovem
6.
J Strength Cond Res ; 34(7): 1867-1874, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32598121

RESUMO

Merrigan, JJ, Tufano, JJ, Fields, JB, Oliver, JM, and Jones, MT. Rest redistribution does not alter hormone responses in resistance-trained women. J Strength Cond Res 34(7): 1867-1874, 2020-The purpose was to examine acute effects of rest redistribution (RR) on perceptual, metabolic, and hormonal responses during back squats. Twelve resistance-trained women (training age 5 ± 2 years; one repetition maximum [1-RM] per body mass, 1.6 ± 0.2) performed traditional (TS, 4 sets of 10 repetitions with 120 seconds interset rest) and RR sets (4 sets of two 5 repetition clusters with 30-second intraset rest and 90-second interset rest) in counterbalanced order, separated by 72 hours. Both conditions were performed at 70% 1RM with 360 seconds of total rest. Ratings of perceived exertion (RPE) were taken after each set. Blood was sampled at baseline, after each set, and at 5, 15, 30, and 60 minutes, as well as 24 and 48 hours after training. Alpha level was p ≤ 0.05. The RPE progressively increased throughout both conditions (p = 0.002) with a greater overall mean for TS (5.81 ± 0.14) than RR (4.71 ± 0.14; p = 0.003). Lactate increased above baseline and remained elevated through 15 minutes post in both conditions (4.00 ± 0.76; p = 0.001), with greater lactate levels for TS (6.33 ± 0.47) than RR (4.71 ± 0.53; p < 0.001). Total testosterone was elevated after set 2 (0.125 ± 0.02; p = 0.011), but no other time point, while free testosterone remained unchanged. Growth hormone continually rose from baseline to set 3 and returned to baseline by 60 minutes post (20.58 ± 3.19). Cortisol and creatine kinase did not change over time. No condition × time interactions existed for any hormone (p > 0.05). Use of rest redistribution resulted in lower perceived effort and lactate responses. Yet, hormone responses during rest redistribution were no different from TS.


Assuntos
Creatina Quinase/metabolismo , Hidrocortisona/metabolismo , Treinamento de Força/métodos , Descanso/fisiologia , Testosterona/metabolismo , Adulto , Creatina Quinase/sangue , Feminino , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/sangue , Ácido Láctico/sangue , Testosterona/sangue , Adulto Jovem
7.
Probiotics Antimicrob Proteins ; 12(4): 1330-1339, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32358640

RESUMO

The fate of dietary protein in the gut is determined by microbial and host digestion and utilization. Fermentation of proteins generates bioactive molecules that have wide-ranging health effects on the host. The type of protein can affect amino acid absorption, with animal proteins generally being more efficiently absorbed compared with plant proteins. In contrast to animal proteins, most plant proteins, such as pea protein, are incomplete proteins. Pea protein is low in methionine and contains lower amounts of branched-chain amino acids (BCAAs), which play a crucial role in muscle health. We hypothesized that probiotic supplementation results in favorable changes in the gut microbiota, aiding the absorption of amino acids from plant proteins by the host. Fifteen physically active men (24.2 ± 5.0 years; 85.3 ± 12.9 kg; 178.0 ± 7.6 cm; 16.7 ± 5.8% body fat) co-ingested 20 g of pea protein with either AminoAlta™, a multi-strain probiotic (5 billion CFU L. paracasei LP-DG® (CNCM I-1572) plus 5 billion CFU L. paracasei LPC-S01 (DSM 26760), SOFAR S.p.A., Italy) or a placebo for 2 weeks in a randomized, double-blind, crossover design, separated by a 4-week washout period. Blood samples were taken at baseline and at 30-, 60-, 120-, and 180-min post-ingestion and analyzed for amino acid content. Probiotic administration significantly increased methionine, histidine, valine, leucine, isoleucine, tyrosine, total BCAA, and total EAA maximum concentrations (Cmax) and AUC without significantly changing the time to reach maximum concentrations. Probiotic supplementation can be an important nutritional strategy to improve post-prandial changes in blood amino acids and to overcome compositional shortcomings of plant proteins. ClinicalTrials.gov Identifier: ISRCTN38903788.


Assuntos
Aminoácidos/sangue , Proteínas na Dieta/sangue , Absorção Intestinal/efeitos dos fármacos , Lactobacillus paracasei/fisiologia , Proteínas de Ervilha/sangue , Probióticos/administração & dosagem , Adulto , Área Sob a Curva , Estudos Cross-Over , Proteínas na Dieta/administração & dosagem , Método Duplo-Cego , Microbioma Gastrointestinal/fisiologia , Humanos , Absorção Intestinal/fisiologia , Masculino , Proteínas de Ervilha/administração & dosagem
8.
Appl Physiol Nutr Metab ; 45(8): 886-892, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32119565

RESUMO

Sports-related concussions (SRC) are traumatic brain injuries induced as the result of a biomechanical force to the body that temporarily impair neurological functions. Not all traumatic impacts reach the threshold necessary to produce concussive symptoms; however, the culmination of these events is known as a subconcussive impact (SCI). Athletes who have been diagnosed with a SRC or those who accumulate multiple SCI have exhibited structural damage to the brain, impairments to learning and memory, and an increase in depressive symptoms. This area is rapidly evolving, and current clinical definitions of injury, diagnosis, and treatment of SRC and SCI are reviewed. In tandem, there is also growing research examining the role of nutrition in brain injuries, focusing primarily on n-3 polyunsaturated fatty acids (PUFA). The potential role of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in reducing inflammation and promoting recovery following brain injury are also reviewed. Overall, advancements in the evaluation of SRC and SCI coupled with n-3 PUFA supplementation show promise in the management of brain injuries, leading to better long-term health outcomes for athletes. Novelty SRC have garnered widespread attention due to the growing body of reported prevalence in youth and professional sports. Current definitions and protocol(s) for diagnosing SRC and SCI have improved, but still require further evaluation. n-3, EPA and DHA, reduce inflammation and promote recovery following brain injuries in experimental models.


Assuntos
Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/terapia , Concussão Encefálica/diagnóstico , Concussão Encefálica/terapia , Ácidos Docosa-Hexaenoicos/uso terapêutico , Ácido Eicosapentaenoico/uso terapêutico , Atletas , Suplementos Nutricionais , Humanos , Incidência
9.
J Clin Densitom ; 23(2): 303-313, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31399322

RESUMO

The purpose of the present study was to generate normative values for total and regional body composition in male and female Division 1 collegiate track and field athletes using dual X-ray absorptiometry. We also sought to examine body composition by event and sex. Data were used from the Consortium of College Athlete Research group. A total of 590 (male [M]/female [F] = 274/316) athletes had their height, weight, total and regional fat mass (FM), lean mass, and bone mineral density (BMD) measured. Athletes were classified into 1 of 7 categories: Jumps (M/F = 28/30); Long Distance (M/F = 104/110), Middle Distance (M/F = 27/24), Multievent (M/F = 11/9), Pole Vault (M/F = 21/27), Sprints (M/F = 54/96), and Throws (M/F = 29/20). Total and regional differences between events and sex were assessed by analysis of variance. Except for male and female throwers, all other track and field athletes' mean percent body fat (M: 10.3%-12.6%, F: 17.5%-21.6%) and visceral FM (<500 g) was low, but in a healthy range. As expected, throwers had significantly (p < 0.05) higher total and regional FM and lean mass than other events. In addition, male (1.55 ± 0.11 g/cm2) and female (1.40 ± 0.12 g/cm2) throwers had significantly greater BMD than all other events while male (1.25 ± 0.10 g/cm2) and female (1.16 ± 0.09 g/cm2) distance runners had significantly lower BMD than all other events. In conclusion, track athletes' body composition differed across events for both males and females. These measurements provide normative data on NCAA Division 1 male and female track and field athletes.


Assuntos
Composição Corporal , Densidade Óssea , Atletismo/fisiologia , Gordura Abdominal/anatomia & histologia , Absorciometria de Fóton , Adolescente , Distribuição da Gordura Corporal , Estatura , Peso Corporal , Calcificação Fisiológica , Comportamento Competitivo/fisiologia , Feminino , Humanos , Masculino , Valores de Referência , Estudos Retrospectivos , Fatores Sexuais , Adulto Jovem
10.
Int J Sports Physiol Perform ; 15(2): 255-261, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31188704

RESUMO

PURPOSE: To examine rest redistribution (RR) effects on back squat kinetics and kinematics in resistance-trained women. METHODS: Twelve women from strength and college sports (5.0 [2.2] y training history) participated in the randomized crossover design study with 72 hours between sessions (3 total). Participants completed 4 sets of 10 repetitions using traditional sets (120-s interset rest) and RR (30-s intraset rest in the middle of each set; 90-s interset rest) with 70% of their 1-repetition maximum. Kinetics and kinematics were sampled via force plate and 4 linear position transducers. The greatest value of repetitions 1 to 3 (peak repetition) was used to calculate percentage loss, [(repetition 10-peak repetition)/(peak repetition) × 100], and maintenance, {100-[(set mean-peak repetition)/(peak repetition)] × 100}, of velocity and power for each set. Repeated-measures analysis of variance was used for analyses (P < .05). RESULTS: Mean and peak force did not differ between conditions. A condition × repetition interaction existed for peak power (P = .049) but not for peak velocity (P = .110). Peak power was greater in repetitions 7 to 9 (P < .05; d = 1.12-1.27) during RR. The percentage loss of velocity (95% confidence interval, -0.22% to -7.22%; P = .039) and power (95% confidence interval, -1.53% to -7.87%; P = .008) were reduced in RR. Mean velocity maintenance of sets 3 (P = .036; d = 1.90) and 4 (P = .015; d = 2.30) and mean power maintenance of set 4 (P = .006; d = 2.65) were greater in RR. CONCLUSION: By redistributing a portion of long interset rest into the middle of a set, velocity and power were better maintained. Therefore, redistributing rest may be beneficial for reducing fatigue in resistance-trained women.


Assuntos
Força Muscular/fisiologia , Treinamento de Força/métodos , Descanso , Esportes/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Cinética , Fadiga Muscular/fisiologia , Caracteres Sexuais , Adulto Jovem
11.
Med Sci Sports Exerc ; 52(5): 1022-1030, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31703023

RESUMO

During a traditional set configuration of resistance exercise (TRD), characterized by a continuous completion of repetitions, a decrease in power output tends to occur throughout a set of repetitions. Inclusion of intraset rest, otherwise known as a cluster set configuration (CLU), counteracts this power decline. However, the effect of a CLU configuration on postexercise myofibrillar protein synthesis rates (MPS) and anabolic signaling has not been investigated. PURPOSE: We aimed to determine if any mechanistic differences exist between TRD and CLU signaling events associated with muscle anabolism. METHODS: In randomized crossover trials, eight resistance-trained participants (23 ± 1 yr, 81 ± 4.7 kg, body fat: 18% ± 1.9%; 1 repetition maximum [1RM], 150 ± 9.1 kg) performed an acute bout of CLU (4 sets × (2 × 5) repetitions, 30-s intraset rest, 90-s interset rest) and TRD (4 sets × 10 repetitions, 120-s interset rest) barbell back squats at approximately 70% 1RM with total volume load equated during primed continuous L-[ring-C6]phenylalanine infusions. Blood and muscle biopsy samples were collected at rest and after exercise at 0, 2, and 5 h. RESULTS: There was no difference in postexercise MPS between the CLU and TRD condition (P > 0.05) and no changes in phosphorylation of mTORC1 downstream targets (p70S6K and 4EBP1). Total and phosphorylated yes-associated protein on Ser127 transiently increased (P < 0.01) immediately after exercise (t = 0) in CLU (~2.1-fold) and TRD condition (~2.2-fold). CONCLUSIONS: Our results show that CLU is a viable anabolic option by preserving power output with similar MPS stimulation when compared with the TRD condition in trained young adults.


Assuntos
Proteínas Musculares/biossíntese , Miofibrilas/metabolismo , Treinamento de Força/métodos , Descanso , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Aminoácidos/sangue , Glicemia/metabolismo , Estudos Cross-Over , Feminino , Humanos , Insulina/sangue , Ácido Láctico/sangue , Sistema de Sinalização das MAP Quinases , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/biossíntese , Percepção/fisiologia , Fosforilação , Esforço Físico/fisiologia , Fatores de Transcrição/biossíntese , Adulto Jovem
12.
Int J Sports Med ; 40(10): 645-649, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31342479

RESUMO

The purpose of this study was to evaluate total, regional, and throwing versus non-throwing arm body composition measures across the 4 major positions of NCAA Division I female softball players using dual X-ray absorptiometry (DXA) (n=128). Total and regional total mass (TM), fat mass (FM), lean mass (LM), bone mineral density (BMD), bone mineral content (BMC), and visceral adipose tissue were measured. Athletes were separated into: pitchers (n=32), catchers (n=13), outfielders (n=39), and infielders (n=44). ANOVA and Tukey's HSD assessed total and regional differences between positions. Although no significant total or regional LM differences were observed across positions, outfielders had significantly (p=0.006-0.047) lower total-body, arm, and trunk TM and FM, leg FM, and leg BMC in comparison to pitchers. The throwing arm had significantly (p<0.0001-0.018) greater LM, BMD, and BMC than the non-throwing arm for all positions. Notably, there were minimal body composition differences among softball positions, with the primary differences being that pitchers had larger total and regional fat values than outfielders. The throwing arm of all positions had greater LM, BMD, and BMC than the non-throwing arm. These values can be used by coaches and trainers as descriptive DXA data for collegiate softball players.


Assuntos
Braço/anatomia & histologia , Atletas , Beisebol , Composição Corporal , Absorciometria de Fóton , Tecido Adiposo , Densidade Óssea , Feminino , Humanos , Universidades , Adulto Jovem
13.
Int J Sports Med ; 40(6): 404-408, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30934090

RESUMO

To examine measures of total and regional body composition using dual X-ray absorptiometry (DXA) in NCAA Division I collegiate equestrian athletes, 31 female collegiate equestrian athletes were matched to a population of normal controls by age and body mass index. Total and regional fat tissue mass (FM), lean tissue mass (LM), bone mineral density (BMD), and abdominal visceral adipose tissue (VAT) were measured by DXA. Equestrian athletes had a significantly (p=0.03) lower total body fat percentage (%fat) than controls. There were no significant differences in total LM and VAT between equestrian athletes and controls. However, equestrian athletes, when compared to the controls, had significantly lower leg %fat, leg FM and higher leg LM. The greater leg LM in equestrian riders resulted in a smaller upper to lower body LM ratio compared to controls. There was no difference in leg BMD between equestrian athletes and controls. There were no significant differences between the 2 styles of riding (i. e., hunt seat and western style) in regards to body composition. The lower total %fat in equestrian athletes seems to be influenced by differences in leg composition, with equestrian athletes having significantly more LM and less FM.


Assuntos
Composição Corporal , Densidade Óssea , Gordura Intra-Abdominal/anatomia & histologia , Esportes/fisiologia , Absorciometria de Fóton , Adolescente , Animais , Índice de Massa Corporal , Feminino , Cavalos , Humanos , Perna (Membro)/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Estudos Retrospectivos , Coluna Vertebral/anatomia & histologia , Adulto Jovem
14.
Int J Sports Med ; 40(7): 447-452, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31013536

RESUMO

This study's purpose was to evaluate total, regional, and throwing versus non-throwing arm body composition measurements between various positions of NCAA Division I male baseball players using dual X-ray absorptiometry (DXA). Two hundred and one collegiate baseball athletes were measured using DXA. Visceral adipose tissue (VAT), total and regional fat mass (FM), lean mass (LM), and bone mineral density (BMD) were measured. Athletes were separated into: pitchers (n=92), catchers (n=25), outfielders (n=43), and infielders (n=41). ANOVA and Tukey's honest significant difference assessed total and regional differences between positions. Infielders had significantly (p<0.05) lower total LM than pitchers and outfielders. Additionally, outfielders had significantly lower total FM compared to pitchers and catchers. No significant differences between positions were observed for total BMD and VAT. Pitchers' and infielders' throwing arm demonstrated significantly greater total mass, FM, LM, and BMD compared to the non-throwing arm. Further, outfielders' throwing arm total mass, LM, and BMD were significantly higher vs. the non-throwing arm. Significant differences were observed in total and regional body composition measurements across position, in addition to differences in throwing arm vs. non-throwing arm composition. These measurement values are important to coaches and trainers as normative positional DXA data for collegiate baseball players.


Assuntos
Braço/anatomia & histologia , Beisebol/fisiologia , Composição Corporal , Absorciometria de Fóton , Tecido Adiposo/anatomia & histologia , Adolescente , Densidade Óssea , Humanos , Masculino , Valores de Referência , Estudos Retrospectivos , Vísceras/anatomia & histologia , Adulto Jovem
16.
J Athl Train ; 54(1): 7-11, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30645147

RESUMO

CONTEXT: The essential omega-3 fatty acids (ω-3 FAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) exhibit vital biological roles and are critical for cardiovascular and neurologic health. Compared with the general population, football athletes may be at an increased risk of cardiovascular disease. Further, those same athletes are also exposed to repetitive head impacts, which may lead to long-term neurologic deficits. Both diets high in ω-3 FAs and supplementation with ω-3 FAs have been reported to reduce the risk of cardiovascular disease, and early evidence suggests a potential neuroprotective effect of supplementation. OBJECTIVE: To determine the (1) erythrocyte content of DHA and EPA, as measured by the Omega-3 Index, expressed as a percentage of total fatty acids, in National Collegiate Athletic Association Division I football athletes and (2) distribution across the Omega-3 Index risk zones established for cardiovascular disease: high risk, <4%; intermediate risk, 4% to 8%; and low risk, >8%. DESIGN: Cross-sectional descriptive study. SETTING: Multicenter trial. PATIENTS OR OTHER PARTICIPANTS: Deidentified data including complete erythrocyte fatty acid profile from the 2017-2018 season, age at time of testing, height, weight, and ethnicity were collected from 404 athletes. MAIN OUTCOME MEASURE(S): Omega-3 Index. RESULTS: About 34% of athletes (n = 138) had an Omega-3 Index considered high risk (<4%), and 66% (n = 266) had a risk considered intermediate (4%-8%). None had a low-risk Omega-3 Index. CONCLUSIONS: The Omega-3 Index is a simple, minimally invasive test of ω-3 FA status. Our data indicate that football athletes may be deficient in the ω-3 FAs DHA and EPA. The fact that no athlete had an Omega-3 Index associated with low risk suggests football athletes may be at increased risk for cardiovascular disease in later life.


Assuntos
Ácidos Graxos Ômega-3/metabolismo , Futebol Americano/fisiologia , Atletas , Estudos Transversais , Dieta , Ácidos Docosa-Hexaenoicos/metabolismo , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/metabolismo , Eritrócitos/química , Feminino , Humanos , Masculino , Estudos Retrospectivos , Universidades , Adulto Jovem
17.
J Strength Cond Res ; 33(4): 902-909, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29470365

RESUMO

Jones, MT, Oliver, JM, Delgado, JC, Merrigan, JJ, Jagim, AR, and Robison, CE. Effect of acute complex training on upper-body force and power in collegiate wrestlers. J Strength Cond Res 33(4): 902-909, 2019-To determine if chain bench press (BP) exercise would enhance acute upper-body force and power, 13 collegiate male wrestlers (mean ± SD; 20.5 ± 1 years; 174.3 ± 4.2 cm; 76.5 ± 8.3 kg) with ≥1 year of strength training participated. Session 1 included body composition ([BodPod] 8.5 ± 2.6% body fat), 3 repetition maximum (RM) BP, and familiarization with the plyometric push-up (PPU) on a force plate. Athletes were matched for 3RM BP and randomly assigned to 1 of 2 groups: Chain BP or Plate BP. One week after session 1, athletes performed the experimental protocol that consisted of: Baseline PPU, Chain/Plate BP set 1 (6 reps @ 60%), 30 seconds rest, PPU, 3 minutes rest, Chain/Plate BP set 2 (6 reps @60%), 30 seconds rest, and PPU. Independent samples t-tests analyzed physical characteristics (p ≤ 0.05). Standardized magnitude-based inferences were used to define outcomes. Aside from age (Plate BP 21.4 ± 0.8, Chain BP 19.9 ± 0.7 years), no physical differences were observed. Performance of Chain BP and Plate BP resulted in a likely (likelihoods of benefit/trivial/harm relative to the threshold for a smallest worthwhile benefit of 89 W: 0.5/9.2/90.3) and very likely (0.1/0.8/99.1) negative effect on peak power output in the PPU after set 1. Chain BP resulted in a likely positive effect on peak force in the PPU after set 1 (smallest worthwhile benefit 13 N: 82.8/16.9/0.3) and set 2 (94.7/5.2/0.1). Chain BP did not result in higher upper-body power over traditional plate loaded resistances.


Assuntos
Força Muscular , Músculo Esquelético/fisiologia , Treinamento de Força/métodos , Levantamento de Peso/fisiologia , Luta Romana/fisiologia , Composição Corporal , Humanos , Masculino , Exercício Pliométrico , Tórax/fisiologia , Extremidade Superior/fisiologia , Adulto Jovem
18.
J Strength Cond Res ; 33(1): 80-88, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30431530

RESUMO

Kreutzer, A, Martinez, CA, Kreutzer, M, Stone, JD, Mitchell, JB, and Oliver, JM. Effect of ACTN3 polymorphism on self-reported running times. J Strength Cond Res 33(1): 80-88, 2019-This investigation examined the effect of ACTN3 genotype on self-reported distance running personal records (PRs). Of 94 (n = 94) recreationally active men and women, 82 (f = 42, m = 40; age: 22.6 ± 4.5 years; body mass index [BMI]: 23.5 ± 3.4 kg·m) reported 1-mile running PRs, whereas 57 (f = 33, m = 24; age: 23.4 ± 5.3 years; BMI: 22.9 ± 9.3 kg·m) reported 5K running PRs. Subjects were grouped by the presence (ACTN3) or absence (ACTN3) of α-actinin-3, as well as by individual genotype (RR, RX, and XX). Among female participants, ACTN3 reported 64.5 seconds faster (p = 0.048) 1-mile PRs compared with their ACTN3 counterparts. No differences were observed when comparing 5K PRs between genotypes. Two one-sided test equivalence testing revealed that none of the effects observed when comparing ACTN3 and ACTN3 were equivalent to zero. Our study confirms a reportedly greater prevalence of XX benefits for endurance performance in females when compared with males but fails to strongly link ACTN3 genotype to endurance performance. Practitioners should continue to be cautious when using genetic information for talent identification and sport selection.


Assuntos
Actinina/genética , Desempenho Atlético/fisiologia , Corrida/fisiologia , Adolescente , Adulto , Feminino , Genótipo , Humanos , Masculino , Resistência Física , Polimorfismo Genético , Autorrelato , Adulto Jovem
19.
J Strength Cond Res ; 33(1): 1-7, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30431534

RESUMO

Askow, AT, Merrigan, JJ, Neddo, JM, Oliver, JM, Stone, JD, Jagim, AR, and Jones, MT. Effect of strength on velocity and power during back squat exercise in resistance-trained men and women. J Strength Cond Res 33(1): 1-7, 2019-The purpose was to examine load-velocity and load-power relationships of back squat in resistance-trained men (n = 20, 21.3 ± 1.4 years, 183.0 ± 8.0 cm, 82.6 ± 8.0 kg, 11.5 ± 5.0% total body fat) and women (n = 18; 20.0 ± 1.0 years; 166.5 ± 6.9 cm; 63.9 ± 7.9 kg, 20.3 ± 5.0% body fat). Body composition testing was performed followed by determination of back squat 1 repetition maximum (1RM). After at least 72 hours of recovery, subjects returned to the laboratory and completed 2 repetitions at each of 7 separate loads (30, 40, 50, 60, 70, 80, and 90% 1RM) in a random order. During each repetition, peak and average velocity and power were quantified using a commercially available linear position transducer. Men produced higher absolute peak and average power and velocity at all loads. When power output was normalized for body mass, significant differences remained. However, when normalizing for strength, no significant differences were observed between sexes. Furthermore, when subjects were subdivided into strong and weak groups, those above the median 1RM produced higher peak power, but only at loads greater than 60% 1RM. It was concluded that differences between men and women may be a result of strength rather than biological sex. Furthermore, training for maximal strength may be an appropriate method to augment maximal power output in those athletes who exhibit low levels of strength.


Assuntos
Força Muscular , Treinamento de Força , Levantamento de Peso/fisiologia , Atletas , Composição Corporal , Feminino , Humanos , Masculino , Postura , Fatores Sexuais , Adulto Jovem
20.
Int J Sports Physiol Perform ; 14(5): 583-589, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30427251

RESUMO

Purpose: To provide a joint-level analysis of traditional (TS) and cluster (CS) set structure during the back-squat exercise. Methods: Eight men (24 [3] y, 177.3 [7.9] cm, 82.7 [11.0] kg, 11.9 [3.5] % body fat, and 150.3 [23.0] kg 1-repetition maximum [1RM]) performed the back-squat exercise (80%1RM) using TS (4 × 6, 2-min interset rest) and CS (4 × [2 × 3], 30-s intraset rest, 90-s interset rest), randomly. Lower-limb kinematics were collected by motion capture, as well as kinetic data by bilateral force platforms. Results: CS attenuated the loss in mean power (TS -21.6% [3.9%]; CS -12.4% [7.5%]; P = .042), although no differences in gross movement pattern (sagittal-plane joint angles) within and between conditions were observed (P ≥ .05). However, joint power produced at the hip increased from repetition (REP) 1 through REP 6 during TS, while a decrease was noted at the knee. A similar pattern was observed in the CS condition but was limited to the hip. Joint power produced at the hip increased from REP 1 through REP 3 but returned to REP 1 values before a similar increase through REP 6, resulting in differences between conditions (REP 4, P = .018; REP 5, P = .022). Conclusions: Sagittal-plane joint angles did not change in either condition, although CS elicited greater power. Differing joint power contributions (hip and knee) suggest potential central mechanism that may contribute to enhanced power output during CS and warrant further study. Practitioners should consider incorporating CS into training to promote greater power adaptations and to mitigate fatigue.


Assuntos
Postura , Treinamento de Força/métodos , Descanso , Levantamento de Peso/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos Cross-Over , Articulação do Quadril/fisiologia , Humanos , Cinética , Articulação do Joelho/fisiologia , Masculino , Adulto Jovem
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