Kinesiology Commons^™

Reliability Of A Barre-Mounted Dynamometer-Stabilizing Device In Measuring Dance-Specific Muscle Performance, Melissa Strzelinksi, Lori Thein Brody, Jo Armour Smith, Shaw Bronner

Physical Therapy Faculty Articles and Research

BACKGROUND: Hand-held dynamometry is considered an efficient, effective, and portable means of objectively measuring lower extremity strength; however, it has yet to be studied specific to dance-relevant muscle performance. Also, dynamometry is often criticized for variability in results based on tester strength and sex. Use of an external stabilizing device has been suggested to minimize differences in outcomes between male and female testers by reducing variability associated with tester strength limitations. Therefore, this study used a barre-mounted, portable dynamometer stabilizing device to improve consistency of results among different testers for assessing hip and lower extremity muscle performance in dance-relevant positions. …

Associations Between Maternal Technology Use, Perceptions Of Infant Temperament, And Indicators Of Mother-To-Infant Attachment Quality, Shawnee Alvarez Guitierrez, Alison K. Ventura

Kinesiology and Public Health

Background: Previous research suggests parents' use of technological devices, such as TV and mobile devices, within family contexts may decrease the quality of parent-child interactions. During early infancy, mothers report engaging with technological devices during infant feeding and care interactions, however, few studies have explored potential associations between maternal technology use and the quality of mother-to-infant attachment.

Aim: To examine associations between maternal technology use during mother-infant interactions and indicators of mother-to-infant attachment during early infancy.

Study design: Cross-sectional survey.

Methods: Mothers (n = 332) of infants aged 2 to 6 months were recruited via MTurk, a crowdsourcing platform, …

Preliminary Investigation Into The Effect Of Actn3 And Ace Polymorphisms On Muscle And Performance Characteristics, John P. Wagle, Kevin M. Carroll, Aaron J. Cunanan, Alexander Wetmore, Christopher Taber, Brad H. Deweese, Kimitake Sato, Charles A. Stuart

Exercise Science Faculty Publications

Preliminary investigation into the effect of ACTN3 and ACE polymorphisms on muscle and performance characteristics. J Strength Cond Res XX(X): 000-000, 2018-The purpose of this investigation was to explore the phenotypic and performance outcomes associated with ACTN3 and ACE polymorphisms. Ten trained men (age = 25.8 ± 3.0 years, height = 183.3 ± 4.1 cm, body mass = 92.3 ± 9.3 kg, and back squat to body mass ratio = 1.8 ± 0.3) participated. Blood samples were analyzed to determine ACTN3 and ACE polymorphisms. Standing ultrasonography images of the vastus lateralis (VL) were collected to determine whole muscle cross-sectional area …

Physical And Lifestyle Factors Influencing Bone Density In Jockeys: A Comprehensive Update Of The Bone Density Status Of Irish Jockeys, Arthur Dunne, Giles Warrington, Adrian Mcgoldrick, Jennifer Pugh, Michael Harrison, Siobhan O'Connor, Gillian O'Loughlin, Sarahjane Cullen

International Journal of Exercise Science

International Journal of Exercise Science 14(6): 324-337, 2021. Compromised bone density in jockeys has previously been identified as an important health and safety concern in horseracing. Despite this, no update on the bone density status in Irish jockeys has been provided in the past decade. The study aimed to conduct a comprehensive update of the current bone density status in professional Irish jockeys and identify possible contributory physical and lifestyle factors. Eighty-five professional male jockeys (flat n = 39; national hunt (NH) n = 46) completed a dual-energy X-ray absorptiometry (DXA) scan for the assessment of body composition and bone …

Effects Of A Vibrating Foam Roller On Ipsilateral And Contralateral Neuromuscular Function And The Hamstring-To-Quadriceps Ratios, Rachel M. Ruggieri, Jared W. Coburn, Andrew J. Galpin, Pablo B. Costa

International Journal of Exercise Science

International Journal of Exercise Science 14(1): 304-323, 2021. The effects of vibrating foam rolling the hamstrings on range of motion (ROM), hamstrings-to-quadriceps (H:Q) ratios, muscle activation, and peak torque (PT) of the quadriceps and hamstrings have yet to be extensively studied. The aim of this study was to investigate the effects of a vibrating foam roller on the hamstrings. Fifteen resistance trained women (mean age ± SD = 22.9 ± 2.0 years, height = 162.7 ± 4.8 cm, body mass = 66.0 ± 9.7 kgs, BMI = 24.9 ± 3.3 kg·m²) participated in five separate testing sessions to …

Effect Of Prenatal Lifestyle Intervention On Maternal Postpartum Weight Retention And Child Body Massindex Z-Score At 36 Months, Suzanne Phelan, Chantelle N. Hart, Elissa Jelalian, Karen Muñoz-Christian, Noemi Alarcon, Angelica Mchugh, Alison K. Ventura, Rena R. Wing

Kinesiology and Public Health

Background/Objectives We previously reported results from a randomized trial showing that a behavioral intervention during pregnancy reduced excess gestational weight gain but did not impact maternal weight at 12 months. We now examine the longer-term effects of this prenatal intervention on maternal postpartum weight retention and toddler body-mass-index z scores (BMIz) over 36 months.

Subjects/Methods Pregnant women (N = 264; 13.7 weeks’ gestation; 41.6% Hispanic) with overweight or obesity were randomized into usual care or prenatal intervention. Anthropometric assessments in mothers and toddlers occurred at baseline, 35 weeks’ gestation and after delivery at 6, 12, 18, 24, and 36 …

Estimating The Lactate Threshold Using Wireless Near-Infrared Spectroscopy And Threshold Detection Analyses, Trent E. Cayot, Shara G. Robinson, Lindsay E. Davis, Paul A. Bender, John R. Thistlethwaite, Craig E. Broeder, Jakob D. Lauver

International Journal of Exercise Science

International Journal of Exercise Science 14(4): 284-294, 2021. The present investigation examined the ability of two threshold detection analyses (maximum distance, Dmax; modified maximum distance, mDmax) in identifying the near-infrared spectroscopy (NIRS) threshold, a lactate threshold (LT) estimate, from exercising tissue oxygen saturation (StO₂) responses. Additionally, the test-retest reliability of exercising StO₂ and total hemoglobin concentration (THC) responses were examined at moderate and peak cycling intensities. Fourteen healthy, recreationally active participants performed maximal incremental step cycling tests (+25 W / 3 minutes) to volitional fatigue on two separate occasions while StO₂ and THC of the vastus …

Different Cooling Strategies Applied During Inter-Set Rest Intervals In High-Intensity Resistance Training, Gilmar J. Esteves, Renato A. Garcia, Paulo H. S. M. Azevedo

International Journal of Exercise Science

International Journal of Exercise Science 14(2): 295-303, 2021. The purpose of this study was to verify whether cooling between sets during high-intensity resistance exercise improves physical performance and to compare performance among different sites of cooling. It is important because delaying the muscular fatigue could improve total volume at a training session which could lead to greater hypertrophy. Nine healthy and recreational resistance training experienced men, performed six tests of a biceps curl exercise on different days. The first test was the one-repetition maximum test (1RM). Following, we applied five sessions, in crossover and randomized (counter-balanced) design. The subjects received …

Efforts On Changing Lifestyle Behaviors May Not Be Enough To Improve Health-Related Quality Of Life Among Adolescents: A Cluster-Randomized Controlled Trial, Alexsandra Da Silva Bandeira, Michael Beets Med, Mph, Phd, Pablo Magno Da Silveira, Marcus Vinicius Veber Lopes, Valter Cordeiro Barbosa Filho, Bruno G.G. Da Costa, Kelly Samara Silva

Faculty Publications

Schools have been the main context for physical activity (PA) and sedentary behavior (SB) interventions among adolescents, but there is inconsistent evidence on whether they also improve dimensions of the health−related quality of life (HRQoL). The aim of this study was to evaluate the effects of a school-based active lifestyle intervention on dimensions of HRQoL. A secondary aim was to verify whether sex, age, and HRQoL at baseline were moderators of the intervention effect. A cluster-randomized controlled trial was conducted at three control and three intervention schools in Florianopolis, Brazil. All students from 7th to 9th grade were invited to …

Getting In: Safe Water Entry Competencies, Kevin Moran Dr, Jennifer Blitvich, Lauren Petrass, Keith Mcelroy

International Journal of Aquatic Research and Education

In high income countries, jumping and diving into water are a small but persistent cause of death and serious injury especially among male youth and young adults. Although water entries maintain a high media profile, little is known about what entry competencies and underlying water safety knowledge youth bring to this practice. Undergraduates enrolled in aquatics (N= 76) completed a survey before attempting 7 entry jumping and diving tasks. While safety attitudes and self-reported behaviours were generally good, considerable variation in practical entry competence was evident. Most completed a deep-water compact jump (87%) and PFD jump (88%) with …

Perceptions Of Water Competencies, Drowning Risk And Aquatic Participation Among Older Adults, Teresa Stanley, Kevin Moran

International Journal of Aquatic Research and Education

New Zealand has an aging population and, despite falling drowning tolls in all other age groups (WSNZ, 2019c), older adults have continued to drown in both increasing numbers and proportion. The reasons for this are not well understood since very little drowning research has focused on older people. A water safety survey (N = 389) seeking information on older adults’ aquatic recreational practices and perceptions of safety was conducted at the end of the summer season, 2019. Most adults (86%, n = 335) reported some aquatic activity in the previous year, but those aged 65+ years (66%) were significantly …

The Lifeguard Rescue Reporting System: Survey Results From A Collaborative Data Collection Method, William D. Ramos, Roy Fielding, Kristina R. Anderson, Peter G. Wernicki Md

International Journal of Aquatic Research and Education

Several water safety organizations have attempted to improve reporting regarding lifeguard actions in order to better understand the characteristics of successful, non-fatal rescues. In 2003, a collective effort initiated the Lifeguard Rescue Reporting System, an online survey distributed to lifeguards and facility managers across the United States and Canada to better understand rescue actions performed in pools/spas, water parks, and open water areas. After seven years of data collection, the online survey accumulated data reflecting 1,676 rescue actions, collecting information including location, victim characteristics and outcome, rescuer characteristics and strategies, and other general circumstances. Descriptive results indicated that at least …

In This Issue (13:2), Stephen J. Langendorfer Ph.D.

International Journal of Aquatic Research and Education

front matter to Volume 13, Issue 2

Water Safety Education Programs In Culturally And Linguistically Diverse Seattle Communities: Program Design And Pilot Evaluation, William A. Koon, Elizabeth Bennett, Sarah Stempski, Jennifer Blitvich

International Journal of Aquatic Research and Education

Drowning is a public health concern that disproportionally affects children and minorities in Washington State. Community health educators from Seattle Children’s Hospital designed a Water Safety Education and Lifejacket Giveaway Program for low-income parents of preschool-aged children from culturally and linguistically diverse backgrounds. The program was interpreted into multiple languages and parents and children in attendance received free lifejackets. The mixed-methods pilot evaluation of this program found statistically significant relationships between language and self-reported parent swim skill level (English-speaker OR 4.6; 95%CI: 1.84 – 11.54); and confidence of keeping one’s child safe (English-speaker OR 3.34; 95%CI: 1.10 – 10.4). Additionally, …

Surfboard Paddling Technique And Neuromechanical Control: A Narrative Review, Wynand Volschenk, Zachary J. Crowley-Mchattan, John W. Whitting, Rudi A. Meir, Alec K. Mckenzie

International Journal of Aquatic Research and Education

Surfboard paddling is an essential activity when surfing. Research investigating surfboard paddling, especially as it pertains to neuromechanical control and techniques used, is limited. Previous research made use of swim ergometers to examine surfboard paddling demands. The validity of using swim ergometers in surfboard paddling research and training deserves further analysis. To establish ecologically valid findings, researchers have begun to use swim flumes and still-water paddling environments to investigate paddling efficiency and technique. This emerging body of research has reported that muscle activation patterns, intensities, and timings differ as surfers move through different paddle stroke phases. A deeper understanding of …

Acute Effects Of Foam Rolling On Cycling Performance: A Randomized Cross-Over Study, Julio Benvenutti Bueno De Camargo, Paulo Henrique Barbosa, Matheus Moraes, Tiago Volpi Braz, Felipe Alves Brigatto, Danillo Rodrigues Batista, Guilherme Businari, Charlini Hartz, Ricardo Simoes, Marcelo Saldanha Aoki, Charles Ricardo Lopes

International Journal of Exercise Science

International Journal of Exercise Science 14(6): 274-283, 2021. Acute foam rolling protocols may increase range of motion without a negative impact on muscle performance. The main purpose of the present study was to investigate the acute effects of foam rolling on cycling performance (mean power and maximal power), affect and perceived exertion. A secondary aim was to assess the effect of foam rolling on post-exercise muscle soreness. In a random order, ten recreationally trained cyclists (age: 26 ± 5 years; height 1.76 ± 0.06 m; total body mass 78.3 ± 19.8 kg; cycling experience: 5.6 ± 5.3 years; 4.1 ± …

Evaluating The Clinical Utility Of Daily Heart Rate Variability Assessment For Classifying Meaningful Change In Testosterone-To-Cortisol Ratio: A Preliminary Study, Justin A. Deblauw, Derek A. Crawford, Brady K. Kurtz, Nicholas B. Drake, Katie M. Heinrich

International Journal of Exercise Science

International Journal of Exercise Science 14(3): 260-273, 2021. The study purpose was to determine the relationship of resting heart rate variability (HRV) and testosterone to cortisol (T:C) ratio, along with the diagnostic ability of HRV to assess changes in T:C ratio during a 9-week high-intensity functional training intervention. Eight recreationally-active men (n = 4, age 24.25 ± 1.75 yrs, height 181.25 ± 3.86 cm, weight 79.68 ± 11.66 kg) and women (n = 4, age 26 ± 3.6 yrs, height 164.25 ± 3.3, weight 73.4 ± 8.42) completed daily HRV measurements (HRVdaily) using photoplethysmography via a commercially-available smartphone …

The Effect Of A Text-Message Based Hydration Education Intervention On Hydration Knowledge And Behavior Of Division I Female Collegiate Soccer Players, Milaena Ferrarese

Theses and Dissertations

There is increasing evidence of athletes entering their training sessions in an already dehydrated state. It is crucial for athletes to properly replenish fluid and electrolytes lost via sweat in order to optimize their training and recovery. The purpose of this study is to assess the effect of a text-message based hydration education intervention on the knowledge and hydration status of division I female collegiate soccer players.A total of 14 participants completed baseline testing, which included hydration knowledge and behavior questionnaires, and pre- and post-practice weights to calculate % weight change (%WC). The participants also provided a baseline urine sample …

Is The Acsm And Friend Metabolic Equations Valid For Assessing Cardiorespiratory Fitness Among 18-34 Aged Men? : Preliminary Results, Marc-Olivier Dugas, Laurie Simard, Tommy Chevrette, Martin Lavalliere

Topics in Exercise Science and Kinesiology

Topics in Exercise Science and Kinesiology Volume 2: Issue 1, Article 2, 2021. Metabolic equations, such as ACSM and FRIEND, are used worldwide to indirectly measure the VO₂max in adults, but lack of accuracy seems to occur. 30 men of 18-34 years old performed a maximal incremental test on a treadmill during which direct VO₂max measurements was taken and then have been compared to ACSM and FRIEND metabolic equations. Point of application #1: Better evaluation and exercise prescription among athletic populations. Point of application #2: Act in prevention among sedentary and symptomatic populations. Point of application …

Mental Health Mobile App Use: Considerations For Serving Underserved Patients In Integrated Primary Care Settings, Margaret R. Emerson, Jennifer Harsh Caspari, Maxine Notice, Shinobu Watanabe-Galloway, Danae Dinkel, Josiane Kabayundo

Journal Articles

Depression, the most commonly experienced mental illness, affects more than 264 million people and is one of the leading causes of disability worldwide [1]. Depression, or major depressive disorder, is characterized by depressed mood and often accompanies other symptoms such as lack of interest, fatigue, feelings of worthlessness, impaired thinking, psychomotor agitation or slowing, thoughts of being better off dead and/or of suicide [2]. According to the 2018 National Survey of Drug Use and Health (NSDUH), 17.7 million or 7.7% of U.S. adults met the criteria for having a major depressive episode in the past year [ …

The Influence Of Education On The Nutritional Knowledge Of Certified Fitness Professionals, Bridget F. Melton, Joelle Romanchik-Cerpovicz, Greg A. Ryan, Catherine Gallagher

International Journal of Exercise Science

International Journal of Exercise Science 14(4): 239-249, 2021. The American Fitness Industry has seen progressive success with recent increases in facility memberships and annual revenues of fitness centers. The number of fitness trainers and instructors in the United States has persisted this growth and is projected to grow over the next decade. However, only a few known studies have investigated the nutritional education of fitness professionals. This preliminary study explores the education and knowledge among certified fitness professions (CFPs) in the United States. A cross-sectional, descriptive survey design was utilized with a convenience sample of 120 female participants from the …

Dark Chocolate Supplementation Elevates Resting Energy Expenditure In Exercise Trained Females, Katie M. Presler, Michael Webster

International Journal of Exercise Science

International Journal of Exercise Science 14(2): 250-259, 2021. Several recent reports have indicated positive health and exercise benefits of (-)-epicatechin-rich cocoa products. This study investigated the influence of dark chocolate (DC) supplementation on resting and steady state exercise metabolism in a group of athletically fit females. Using a randomized, single-blind design, 18 exercise trained female subjects were assigned to a 30-d supplementation with either 20g· d^-1 of 70% DC (n = 9) or a calorically matched white chocolate (WC) (n = 9). Pre-supplementation (PRE), subjects underwent indirect calorimetry assessment for resting energy expenditure (REE) and exercise energy …

Beauty That Moves: Dance For Parkinson’S Effects On Affect, Self-Efficacy, Gait Symmetry, And Dual Task Performance, Cecilia Fontanesi, Joseph F. X. Desouza

Publications and Research

Background: Previous studies have investigated the effects of dance interventions on Parkinson’s motor and non-motor symptoms in an effort to develop an integrated view of dance as a therapeutic intervention. This within-subject study questions whether dance can be simply considered a form of exercise by comparing a Dance for Parkinson’s class with a matched-intensity exercise session lacking dance elements like music, metaphorical language, and social reality of art-partaking.

Methods: In this repeated-measure design, 7 adults with Parkinson’s were tested four times; (i) before and (ii) after a Dance for Parkinson’s class, as well as (iii) before and (iv) after a …

Développement D’Un Outil Personnalisé D’Aide À La Décision En Vue De Minimiser Les Risques En Manutention Impliquant Des Postures Symétriques Et Asymétriques, Aboulfazl Shirazi-Adl, Navid Arjmand, André Plamondon

Rapports de recherche scientifique

Les charges excessives imposées sur la colonne vertébrale lombaire constituent un facteur de risques important pour les maux de dos. La modélisation biomécanique de la colonne vertébrale est la seule approche non invasive permettant d’estimer ces charges, mais la complexité de ces modèles limite leur utilisation par des ergonomes. Pour aider ces derniers à identifier des situations à risque de blessures au dos afin de limiter le chargement aux structures lombaires, il existe des outils d’aide à la décision comme l’équation de levage du NIOSH (Revised NIOSH Lifting Equation, Waters et al., 1993) ainsi que les tables …

A Vicious Cycle Of Fear Of Falling Avoidance Behavior In Parkinson’S Disease: A Path Analysis, Merrill R. Landers, Kameron M. Jacobson, Nicole E. Matsunami, Hannah E. Mccarl, Michelle T. Regis, Jason K. Longhurst

Integrated Health Sciences Faculty Research

Background: Postural instability (PI) in Parkinson's disease (PD) is associated with several negative downstream consequences. Objective: The purpose was to explore the validity of a theoretical model of these downstream consequences arranged in a vicious cycle wherein PI leads to decreased balance confidence, which in turn leads to increased fear of falling (FOF) avoidance behavior, which in turn leads to decreased physical conditioning, which then feeds back and negatively affects PI. Methods: A path analysis of cross-sectional data from 55 participants with PD was conducted. The four constructs in the model connected in succession were: 1. PI (principal components analysis …

Activation Of Orexin 1 Receptors In The Paraventricular Nucleus Contributes To The Development Of Deoxycorticosterone Acetate-Salt Hypertension Through Regulation Of Vasopressin, Jeremy Bigalke, Huanjia Gao, Qing Hui Chen, Zhiying Shan

Michigan Tech Publications, Part 1

Salt-sensitivity is a major factor in the development of hypertension. The brain orexin system has been observed to play a role in numerous hypertensive animal models. However, orexin’s role in the pathology of salt-sensitive hypertension (SSH) remains to be adequately explored. We assessed the impact of orexin hyperactivity in the pathogenesis of the deoxycorticosterone acetate (DOCA) – salt rat model, specifically through modulation of Arginine Vasopressin (AVP). Adult male rats were separated into three groups: vehicle control, DOCA-salt, and DOCA-salt+OX1R-shRNA. DOCA-salt rats received subcutaneous implantation of a 21-day release, 75 mg DOCA pellet in addition to saline drinking water (1% …

Female Mice May Have Exacerbated Catabolic Signalling Response Compared To Male Mice During Development And Progression Of Disuse Atrophy, Megan E. Rosa-Caldwell, Seongkyun Lim, Wesley A. Haynie, Jacob L. Brown, John William Deaver, Francielly Morena Da Silva, Lisa T. Jansen, David E. Lee, Michael P. Wiggs, Tyrone A. Washington, Nicholas P. Greene

Health & Kinesiology Faculty Publications and Presentations

Background: Muscle atrophy is a common pathology associated with disuse, such as prolonged bed rest or spaceflight, and is associated with detrimental health outcomes. There is emerging evidence that disuse atrophy may differentially affect males and females. Cellular mechanisms contributing to the development and progression of disuse remain elusive, particularly protein turnover cascades. The purpose of this study was to investigate the initial development and progression of disuse muscle atrophy in male and female mice using the well-established model of hindlimb unloading (HU). Methods: One hundred C57BL/6J mice (50 male and 50 female) were hindlimb suspended for 0 (control), 24, …

Material Properties And Application Of Biomechanical Principles Provide Significant Motion Control Performance In Experimental Ankle Foot Orthosis-Footwear Combination, Christopher F. Hovorka, Géza F. Kogler, Young Hui Chang, Robert Gregor

Kinesiology and Nutrition Sciences Faculty Research

© 2021 The Author(s) Background: This study, the first of its kind, originated with the need for a brace (an ankle foot orthosis), to constrain ankle plantarflexion and dorsiflexion within a motion threshold of < 5°. A conventional thermoplastic, solid brace failed during a quasi-static loading study, informing the investigation and development of an experimental carbon composite brace, maximizing stiffness and proximity of shank and foot cylindrical shells to provide the required degree of control. Methods: Two experiments were conducted: a quasi-static loading study, using cadaveric limbs (n = 2), and a gait study with healthy subjects (n = 14). Conditions tested were STOP, FREE, and CONTROL. Data for all studies were collected using six motion-capture cameras (Vicon, Oxford, UK; 120 Hz) tracking bone-anchored markers (cadaveric limbs) and skin-anchored markers (subjects). In the quasi-static loading study, loading conditions were congruent with the gait study. Study 1 involved a quasi-static loading analysis using cadaveric limbs, compared motion data from a conventional thermoplastic solid brace and the experimental brace. Study 2 involved quantifying ankle plantarflexion and dorsiflexion in subjects during treadmill walking, in brace STOP, FREE, and CONTROL conditions. Findings: The experimental brace in STOP condition consistently constrained ankle plantarflexion and dorsiflexion below the motion threshold of < 5°, across all studies. Interpretation: Collectively, these findings demonstrate (1) that a conventional thermoplastic, solid brace was ineffective for clinical applications that required significant motion control, and (2) that ankle motion control is most effective when considered as a relationship between the brace, the ankle-foot complex, and the external forces that affect them both.

Perspectives Of Infant Active Play: A Qualitative Comparison Of Working Versus Stay-At-Home Parents, Kailey Snyder, John Rech, Kimberly Masuda, Danae Dinkel

Journal Articles

Background: Parents play a key role in infant’s development through their interactions and the type of environment they provide to promote active play. The amount of time parents are able to spend with their infant is dependent on their working status, yet few studies have explored parent perception of their infant’s active play by working status. The purpose of this study was to explore parent perception of active play and compare responses between working and stay-at-home parents. Methods: Twenty-nine parents participated in this qualitative study by completing a one-time, in-person semistructured interview based on the Theory of Planned Behavior. Themes …

Ultrasound Measurements Of Subcutaneous Fat Thickness Are Robust Against Hydration Changes, Dale R. Wagner, James D. Cotter

Kinesiology and Health Science Faculty Publications

Ultrasound is an appealing tool to assess body composition, combining the portability of a field method with the accuracy of a laboratory method. However, unlike other body composition methods, the effect of hydration status on validity is unknown. This study evaluated the impact of acute hydration changes on ultrasound measurements of subcutaneous fat thickness and estimates of body fat percentage. In a crossover design, 11 adults (27.1 ± 10.5 years) completed dehydration and hyperhydration trials to alter body mass by approximately ±2%. Dehydration was achieved via humid heat (40 °C, 60% relative humidity) with exercise, whereas hyperhydration was via ingestion …