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Ultrasound Measured Flexor Muscle Thickness in the Forearms of Rock Climbers
Title
Ultrasound Measured Flexor Muscle Thickness in the Forearms of Rock Climbers.
Creator
Marsala, Michael, Garcia, Jeanette, Fukuda, David, Stock, Matt, University of Central Florida
Abstract / Description
PURPOSE: To examine differences in the forearms of rock climbers using ultrasound to measure the muscle thickness of the finger flexors. METHODS: A total of 33 participants were recruited, 22 climbers (22.23 years; 68% male) and 11 controls (21.8; 55% male). Climbers provided self-reported ratings of their climbing ability, skill level, and preferred mode of climbing (e.g. sport climbing vs. bouldering). Anthropometric measures, including body fat percentage, were measured in all participants...
Show morePURPOSE: To examine differences in the forearms of rock climbers using ultrasound to measure the muscle thickness of the finger flexors. METHODS: A total of 33 participants were recruited, 22 climbers (22.23 years; 68% male) and 11 controls (21.8; 55% male). Climbers provided self-reported ratings of their climbing ability, skill level, and preferred mode of climbing (e.g. sport climbing vs. bouldering). Anthropometric measures, including body fat percentage, were measured in all participants. Ultrasound measurements were taken with the participant lying on their back on a padded table with their dominant hand supinated. Muscle thickness measurements were taken at the forearm where a peak of the forearm flexors was identified on the medial aspect of the forearm after a circumference measurement and small mark was made. The distance from the ulna and radius to the muscle-skin interface was measured, as well as echo intensity surrounding the median nerve using a third party program. RESULTS: Approximately 50% of climbers rated themselves as (")intermediate("), and the other 50% rated themselves as (")advanced(") climbers, while 77% of the 22 climbers classified themselves as primarily (")sport climbers("), and 23% classified themselves as (")boulderers("). Body fat percentages were significantly different at 19.14(&)#177;6.99 and 30.02(&)#177;7.6 for climbers and controls. Ulnar and radial muscle thickness values were significantly higher in climbers, 4.23(&)#177;.39and 2.32(&)#177;.39, respectively, and 3.61(&)#177;.6 and 1.84(&)#177;.31 in controls (p(<).001). No differences in echo intensity were observed between climbers and non-climbers. DISCUSSION: The findings suggests that there are differences in flexor muscle thickness observed in earlier stages of rock climbing. Echo intensity of the flexor muscles were also measured, however significant variance in results warrants further investigation. Future studies should consider larger samples to better determine differences among muscle thickness and echo intensity across climbing abilities and mode of climbing, thus allowing for more specific training programs to be developed at each phase of training.
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Date Issued
2019
Identifier
CFE0007677, ucf:52473
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007677
Role of brain derived neurotrophic factor (BDNF) in stimulating strength improvements induced by short-term resistance training
Title
Role of brain derived neurotrophic factor (BDNF) in stimulating strength improvements induced by short-term resistance training.
Creator
Church, David, Hoffman, Jay, Stout, Jeffrey, Fukuda, David, Stock, Matt, University of Central Florida
Abstract / Description
Strength adaptations from short-term resistance training are thought to be related primarily to neurological adaptations. Considering brain-derived neurotrophic factor (BDNF) role in the nervous system, it is possible that BDNF has a role in these adaptations. Fourteen untrained males were randomized into either a resistance training (RT; n =8) or control (CON; n=6) group. Motor unit (MU) recruitment at 50% and 80% of each participant's maximal voluntary isometric contraction (MVIC), muscle...
Show moreStrength adaptations from short-term resistance training are thought to be related primarily to neurological adaptations. Considering brain-derived neurotrophic factor (BDNF) role in the nervous system, it is possible that BDNF has a role in these adaptations. Fourteen untrained males were randomized into either a resistance training (RT; n =8) or control (CON; n=6) group. Motor unit (MU) recruitment at 50% and 80% of each participant's maximal voluntary isometric contraction (MVIC), muscle cross sectional area (CSA) and thickness (MT), as well as one-repetition maximum (1RM) of the squat (SQT), leg press (LP), and leg extension (LE) were performed before (PRE) and after (POST) the training period. Following the MU assessment, the recruitment threshold (RT; % MVIC) and mean firing rate (MFR; pulse per second [pps]) of each MU were determined. Linear regression was used to quantify the slope (pps/% MVIC) and y-intercept (pps) of the MFR versus RT relationship for each participant and time point. Participants completed an acute resistance exercise bout at PRE and POST consisting of 3 sets of 8 (-) 10 repetitions with 90 seconds of rest between each set of SQT, LP, and LE. Blood samples were obtained following a 4-hour fast before (BL), immediately-(IP), and one-(1H) hour post resistance exercise. RT subjects performed the same resistance exercise protocol at PRE twice a week for 3-weeks. CON subjects were instructed to not perform any resistance exercise. Area under the curve (AUC) analysis was determined by the trapezoidal method. Pearson product-moment correlations were used to examine selected bivariate relationships. The ?BDNF AUC was significantly correlated to the relative 80% ?y-intercept (r=-0.626, p=0.030), and trended to be correlated to the relative 80% ?slope (r=0.551, p=0.063). Our results indicate that ? in plasma BDNF concentrations appear to be related to ?'s MU recruitment at high intensities (80% of MVIC) of exercise.
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Date Issued
2018
Identifier
CFE0006988, ucf:51665
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006988
Mechanical and physical characteristics of knee flexors and extensors following different warm up protocols in collegiate male soccer athletes
Title
Mechanical and physical characteristics of knee flexors and extensors following different warm up protocols in collegiate male soccer athletes.
Creator
Redd, Mike, Fukuda, David, Stout, Jeffrey, Garcia, Jeanette, Wells, Adam, Stock, Matt, University of Central Florida
Abstract / Description
PURPOSE: To compare potential differences in mechanical and physical characteristics of knee flexors and extensors in collegiate male soccer players following different warm up protocols.METHODS: Sixteen collegiate male soccer players (20.33 (&)#177; 1.33 years, 176.97 (&)#177; 6.72 cm, and 78.43 (&)#177; 7.42 kg) participated in this study. A small sided games warm up (SSG), a dynamic warm up (DYN), and a plyometric warm up (PLY) were completed using a randomized crossover design....
Show morePURPOSE: To compare potential differences in mechanical and physical characteristics of knee flexors and extensors in collegiate male soccer players following different warm up protocols.METHODS: Sixteen collegiate male soccer players (20.33 (&)#177; 1.33 years, 176.97 (&)#177; 6.72 cm, and 78.43 (&)#177; 7.42 kg) participated in this study. A small sided games warm up (SSG), a dynamic warm up (DYN), and a plyometric warm up (PLY) were completed using a randomized crossover design. Tensiomyography (TMG) was used to assess contraction time (Tc), delay time (Td) and maximal displacement (Dm) of the rectus femoris (RF) and biceps femoris (BF) of both legs before (PRE) and after (POST) each warm up. POST assessment included: TMG of the RF and BF, countermovement jump height (CMJ-h), CMJ flight time (CMJ-ft), 20m sprint time (20m), T-test time, and sit and reach (SR) distance. All TMG measures were analyzed using a three-way [condition (&)#215; time x leg] analysis of variance (ANOVA). All performance variable data were analyzed with a repeated measures ANOVA.RESULTS: There was no difference between warm up protocols for T-test, CMJ-h, or CMJ-ft. 20m significantly improved following SSG (p=0.020) compared to DYN and PLY. SR was significantly greater following PLY (p=0.022). Three-way ANOVA did not reveal a significant interaction for any of the measured TMG variables. However, main effects of time were seen PRE to POST for BF-Tc (p=0.035), RF-Td (p(<)0.001) and BF-Td, (p=0.008) and a main effect of condition was seen for RF-Tc (p=0.038).CONCLUSION: Warm-up specific improvements were demonstrated in sprint speed and flexibility measures following SSG and PLY, respectively. While no differences were shown between the examined protocols, the present study revealed PRE to POST changes in certain TMG measures (RF-Td, BF-Td, and BF-Tc) following a warm up in male collegiate soccer athletes.
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Date Issued
2018
Identifier
CFE0007240, ucf:52224
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007240