The purpose of this investigation was to cross-validate the ithlete™ heart rate variability smart phone application with an electrocardiograph for determining ultra-short-term root mean square successive R-R intervals. intervals simultaneously determined via and at rest in twenty five healthy participants. There were no significant differences between derived interval values (p > 0.05) correlation near perfect (r = 0.99, p < 0.001). In addition, revealed a Standard Error Estimate 1.47 Bland...

The purpose of this investigation was to determine the agreement between multifrequency bioelectrical impedance analysis (BIA) and dual-energy x-ray absorptiometry (DXA) for measuring body fat percentage (BF%), fat-free mass (FFM), total segmental lean soft tissue (LST) in collegiate female athletes. Forty-five athletes (age = 21.2 ± 2.0 years, height 166.1 7.1 cm, weight 62.6 9.9 kg) participated study. Variables measured through BIA DXA were as follows: BF%, FFM, LST arms (ARMS(LST)), legs...

Monitoring individual responses throughout training may provide insight to coaches regarding how athletes are coping the current program. It is unclear if evolution of heart rate variability (HRV) in team-sport can be useful providing early indications adaptation. This study evaluated relationships between changes resting cardiac autonomic markers derived from a novel smartphone device within first 3 weeks 5-week conditioning program and eventual change intermittent running performance at...

Snarr, RL and Esco, MR. Electromyographical comparison of plank variations performed with without instability devices. J Strength Cond Res 28(11): 3298–3305, 2014—Although there are multiple studies involving abdominal musculature activation devices (e.g., Swiss balls), is minimal research comparing them a suspension device TRX). The purpose this investigation was to measure the electromyographical (EMG) activity rectus abdominis (RA), external oblique (EO), erector spinae while performing...

Summary Resting heart rate variability ( HRV ) is a potentially useful marker to consider for monitoring training status in athletes. However, traditional data collection methodology requires 5‐min recording period preceded by stabilization period. This lengthy process may limit the field due time constraints and high compliance demands of Investigation into more practical acquisitions required. The aim this study was determine course ECG ‐derived ln RMSSD from recordings. Ten‐minute supine...

Purpose: This study evaluated the 7-d mean and coefficient of variation (CV) supine standing ultrashort log-transformed root square successive R-R intervals multiplied by 20 (lnRMSSDx20) obtained with a smartphone application (app) in response to varying weekly training load (TL). In addition, authors aimed determine if these values could be accurately assessed as few 5 or 3 d/wk. Methods: Nine women from college soccer team performed daily heart-rate-variability measures an app positions...

Abstract Flatt, AA, Esco, MR, and Nakamura, FY. Individual heart rate variability responses to preseason training in high level female soccer players. J Strength Cond Res 31(2): 531–538, 2017—The purpose of this study was track changes load (TL) recovery status indicators throughout a 2-week interpret the meaning these on an individual basis among 8 division-1 Weekly averages for (logarithm root mean square successive R-R interval differences [lnRMSSD]), TL, psychometrics were compared with...

Heart rate variability (HRV) is an objective physiological marker that may be useful for monitoring training status in athletes. However, research aiming to interpret daily HRV changes female athletes limited. The objectives of this study were: 1) assess (i.e., log-transformed root mean square successive R-R interval differences, lnRMSSD) trends both as a team and intra-individually response varying load (TL); 2) determine relationships between lnRMSSD fluctuation (coefficient variation,...

There is very limited scientific data concerning suspension training. The purpose of this investigation was to compare the electromyographic activity pectoralis major, anterior deltoid, and triceps brachii between a push-up traditional push-up. Twenty-one apparently healthy men (n = 15, age 25.93 ± 3.67 years) women 6, 23.5 1.97 volunteered participate in study. All subjects performed four repetitions where order exercises randomized. mean peak normalized electromyography were compared...

This study aimed to compare the weekly natural log of root-mean-square difference successive normal inter-beat (RR) intervals (ln RMSSDWeekly) and its coefficient variation RMSSDCV) in response 5 weeks preseason training professional male futsal players. A secondary aim was assess relationship between ln RMSSDWeekly RMSSDCV. The RMSSD is a measure cardiac–vagal activity, RMSSDCV represents perturbations cardiac autonomic homeostasis, which may be useful for assessing how athletes are coping...

The primary aim of this study was to determine the association between body composition and performance outcomes in youth soccer players. Twenty-five competitive male players (age = 13.7 ± 0.8 years, height 167.4 9.7 cm, weight 57.6 12.1 kg) volunteered participate study. Height were used calculate mass index (BMI). Body fat percentage (BF%) fat-free (FFM) determined with dual-energy X-ray absorptiometry. Each athlete performed Pacer test, vertical jump, t-test drill. Participants...

The purpose of this study was to determine the inter- and intra-testing reliability newly developed tests change direction speed (CODS) reactive agility (RAG) in competitive futsal players. Additionally, were evaluated for their validity with regard differentiation two performance-levels. Thirty-two professional male players (age = 26.22 ± 5.22 years; body height 182.13 5.99 cm, mass 77.43 8.00 kg) participated study. sample divided into groups based on level performance: A top-level-group...

Nakamura, FY, Pereira, LA, Esco, MR, Flatt, AA, Moraes, JE, Cal Abad, CC, and Loturco, I. Intraday interday reliability of ultra-short-term heart rate variability in rugby union players. J Strength Cond Res 31(2): 548-551, 2017-The aim this study was to examine the intraday vagal-related (HRV) elite Forty players from Brazilian National Rugby Team volunteered participate study. The natural log root mean square successive RR interval differences (lnRMSSD) assessments were performed on 4...

The aim of this study was to determine whether the early response in weekly measures HRV, when derived from a smartphone application, were related eventual change VO2max following an off-season training program female soccer athletes. 9 collegiate players participated 11-week conditioning program. In week immediately before and after program, each participant performed test on treadmill maximal oxygen consumption (VO2max). Daily log-transformed root mean square successive R-R intervals...

Esco, MR, Flatt, AA, and Nakamura, FY. Agreement between a smartphone pulse sensor application electrocardiography for determining lnRMSSD. J Strength Cond Res 31(2): 380-385, 2017-The purpose of this study was to determine the agreement finger (SPFS) (ECG) ultra-short-term heart rate variability in 3 different positions. Thirty college-aged men (n = 15) women volunteered participate study. Sixty-second measures were simultaneously taken with SPFS ECG supine, seated, standing The log...

Flatt, AA, Esco, MR, Allen, JR, Robinson, JB, Earley, RL, Fedewa, MV, Bragg, A, Keith, CM, and Wingo, JE. Heart rate variability training load among National Collegiate Athletic Association Division 1 college football players throughout spring camp. J Strength Cond Res 32(11): 3127-3134, 2018-The purpose of this study was to determine whether recovery cardiac-autonomic activity baseline occurs between consecutive-day sessions positional groups a collegiate team during Spring A secondary aim...

Abstract Nakamura, FY, Antunes, P, Nunes, C, Costa, JA, Esco, MR, and Travassos, B. Heart rate variability changes from traditional vs. ultra–short-term recordings in relation to preseason training load performance futsal players. J Strength Cond Res 34(10): 2974–2981, 2020—The aims of this study were analyze heart (HRV) players during using both “criterion” (10-minute) ultra-shortened (2-minute) measures, determine whether they related the Yo-Yo Intermittent Recovery Test, level 1 (Yo-Yo...