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Accuracy of Self-Reported Height, Weight, and Calculated BMI and Resulting FITNESSGRAM® Healthy Fitness Zone Classification

Description: The determination of adiposity in adolescents is often assessed with calculations of body mass indices (BMI). Researchers often obtain these measurements from self-reported (SR) values. The purpose of this study was to determine the accuracy of SR height, weight, and calculated BMI (from height and weight). SR and actual measured (ME) BMI values were compared with standards from the FITNESSGRAM® Healthy Fitness Zone (HFZ) classifications. SR height and calculated BMI were found to be accurate while SR weight was, on average, underreported by 4.77 lbs. Because of these errors in SR height and weight, accuracy of classification into the FITNESSGRAM® HFZ was compromised. Consequently, it is important that researchers ascertain actual values of height and weight when measuring adolescents rather than use those from self-reports.
Date: May 2006
Creator: Rowell, Chelsie Joyce

The Construct Validity of Self-Reported Historical Physical Activity

Description: The purpose of this study was to determine the construct validity of self-reported historical walking, running, and jogging (WRJ) activity. The criterion measure was concurrent performance on a maximal treadmill test. Subjects completed a medical exam and treadmill test between the years 1976 and 1985, and completed a follow-up questionnaire in 1986. Questionnaire included an item that assessed WRJ for each year from 1976 through 1985. Data analysis included Spearman correlations, partial correlations, ANOVA, and ANCOVA. Results indicated self-reported historical WRJ can be assessed with reasonable validity when compared with concurrently measured treadmill performance, and there is no decay in the accuracy of this reporting for up to ten years in the past.
Date: May 2002
Creator: Bowles, Heather R.

Effect of Chronic Alcohol Abuse and Resistance Training on the Skeletal Muscle Androgen Receptor Concentration of Rats

Description: The purpose was to examine the effect of chronic alcohol abuse on the androgen receptor content (AR) in skeletal muscle, and to determine if this effect was influenced by resistance training. Thirty-four male rats (456 ± 1 g; mean ± SE) were divided into 4 groups: Sham exercise-Ethanol, Sham exercise-Normal diet, Exercise-Ethanol, and Exercise-Normal diet. Both Exercise groups underwent a 6-week "squat" resistance training protocol and both Ethanol groups received an alcohol-rich diet throughout the 6-week period. Western blot analysis showed no effect of alcohol or resistance training on the AR of the extensor digitorum longus. For the rectus femoris, alcohol caused a decline in the AR (p=0.01). This reduction was not attenuated by resistance training. The AR of the soleus was not affected by chronic alcohol abuse alone; however, the resistance training induced increase in the AR was prevented by chronic alcohol abuse (p=0.03).
Date: August 2004
Creator: Vingren, Jakob L.

The Effect of Steroid Dose Regimen on the Relationship Between Lower Extremity Muscle Function and Cardiac Function in Post Heart Transplant Patients

Description: Differences in cardiovascular/aerobic function in heart transplant patients might be attributed to the rate of corticosteroid withdrawal and/or to skeletal muscle function. This hypothesis was tested among nine male, cardiac transplant recipients. Prednisone dosage was monitored, and isokinetic strength testing was performed at 4 different time periods throughout the first year post-transplantation. Cardiovascular/aerobic measurements were obtained at the fourth time period. Pre-surgery characteristics were obtained from the patient's medical record. Significant Pearson-product moment correlations were only found between muscle function and aerobic function and between pre-surgery characteristics and cardiovascular/aerobic performance. The results of this study show no evidence that rapid reduction of prednisone dosage enhances aerobic function by benefiting skeletal muscle function.
Date: May 2001
Creator: Galatas, Mary V.

The Effects of Motivational and Instructional Self Talk on the Attentional Focus of High School Distance Runners.

Description: The purposes of this study were to examine the (a) attentional focus strategies used by high school distance runners, (b) changes in attentional focus across four laps in three 1.6 km runs, and (c) effects of a pre-performance intervention using motivational and instructional self talk on the attentional focus strategies used by and performance of high school distance runners. Participants (N = 42) completed a background and demographic questionnaire, the Cross Country Attentional Focus Inventory (CCAFI), a motivational and instructional statement survey, and the Self-Motivation Inventory. A series of oneway ANOVAs revealed significant differences in the types of attentional strategies used by each group, as well as fluctuations in use of strategies. The experimental group associated more during the each of the 1.6 km trials, whereas the control group dissociated more throughout each trial. A significant group by week interaction was found, with the experimental group maintaining their performance and the control group slowing from week one to week three.
Date: May 2005
Creator: Burgess, Amber G.

Evaluating the Pulse Sensor as a Low-Cost and Portable Measurement of Blood Pulse Waveform

Description: This study was aimed at determining whether the digital volume pulse waveform using the Pulse Sensor can be used to extract features related to arterial compliance. The Pulse Sensor, a low-cost photoplethysmograph, measures green light reflection in the finger and generates output, which is indicative of blood flow and can be read by the low-cost Arduino UNO™. The Pulse Sensor code was modified to increase the sampling frequency and to capture the data in a file, which is subsequently used for waveform analysis using programs written in the R system. Waveforms were obtained using the Pulse Sensor during two 30-s periods of seated rest, in each of 44 participants, who were between the ages of 20 and 80 years. For each cardiac cycle, the first four derivatives of the waveform were calculated and low-pass filtered by convolution before every differentiation step. The program was written to extract 19 features from the pulse waveform and its derivatives. These features were selected from those that have been reported to relate to the physiopathology of hemodynamics. Results indicate that subtle features of the pulse waveform can be calculated from the fourth derivative. Feature misidentification occurred in cases of saturation or low voltage and resulted in outliers; therefore, trimmed means of the features were calculated by automatically discarding the outliers. There was a high efficiency of extraction for most features. Significant relationships were found between several of the features and age, and systolic, diastolic, and mean arterial blood pressure, suggesting that these features might be employed to predict arterial compliance. Further improvements in experimental design could lead to a more detailed evaluation of the Pulse Sensor with respect to its capability to predict factors related to arterial compliance.
Date: May 2016
Creator: Smithers, Breana Gray

Perceived Submaximal Leg Extension Forces of Young Adult Males

Description: The purpose was to examine actual force (AF) productions of males for accuracy during leg extensions when given a random desired force (DF) ranging from 10-90% of maximal force (MF). Thirty males ranging from 18 to 30 years of age (M = 21.99 + 3.04), who had no previous experience with the test equipment, went through 9 randomly ordered submaximal efforts followed by a maximal effort. Correlations between AF and DF were high (r > .79) and test-retest was consistent between AF (r = .87) and MF (r = .90). Participants consistently undershot DF on both test and retest from 20-90% and overshot DF only at 10%. Power functions revealed exponents of less than 1, indicating that AF grows slower then DF for both test .70 (.95 CI = .63 - .77) and retest .66 (.95 CI = .60 - .73). The results replicate a prior study by Jackson, Martin, Koziris, Ludtke, and Dishman (2001) that used incremental rather than random increases in DF.
Date: August 2001
Creator: Ludke, Andrew William

Treadmill validation of the Siconolfi step test.

Description: Maximal oxygen uptake (VO2max) is the internationally recognized measure of a person's cardiorespiratory fitness. Currently the most accurate way of assessing one's true VO2max involves the use of maximal exercise tests, which require the use of specialized equipment, and are time consuming and costly. The purpose of this study was to determine the validity of the submaximal Siconolfi step test to estimate VO2max. A second purpose was to determine if body fat percentage improved the validity. Thirty-six individuals underwent a maximal treadmill test, in which VO2max was directly measured, and the step test. Results indicate that, although VO2max estimates generated by the Siconolfi step test are highly correlated to true VO2max (r =.887; p<.01), the values consistently underestimated a person's aerobic fitness. It was also determined that body fat percentage did not contribute to the prediction of VO2max.
Date: May 2005
Creator: Harkrider,Tiffani L.