Showing papers by "Minsoo Kang published in 2022"

Muscle thickness assessment of the forearm via ultrasonography: is experience level important?

Abstract: It is suggested that experience is needed in order to capture valid estimates of muscle size with ultrasound. However, it is unknown whether there is a large degree of skill needed to analyze the images once they are captured. Objective. To determine if less experienced raters could accurately analyze ultrasound images of the forearm by comparing their estimates with those of a very experienced ultrasonographer (criterion). Approach. 50 muscle thickness images were captured by one experienced ultrasonographer (also Rater 1). Those images were saved and were then measured by four raters with different levels of experience. The rater who captured the images was very experienced (criterion), the second rater was also experienced and provided 5 minutes of instruction for Rater 3 (minimal experience) and Rater 4 (no experience). Test-retest reliability was also determined for Rater 3 and 4. Main Results. The average muscle thickness value for the criterion was 3.73 cm. The constant error for Rater 2, 3, and 4 was −0.003 (0.02) cm (p = 0.362), −0.07 (0.04) cm (p < 0.001), and 0.02 (0.09) cm (p = 0.132), respectively. The SD for Rater 4 was greater, resulting in wider limits of agreement compared to Rater 2 and 3. Absolute error was 0.01 cm for Rater 2, whilst it was 0.07 cm and 0.03 cm for the two inexperienced raters (Rater 3 and 4). The error for Rater 3 was systematic and post-hoc assessment found that this rater was using a different border than the other three raters (but consistent across time). For the test-retest reliability, the minimal difference for Rater 3 was 0.08 cm (relative minimal difference of 2%) and 0.17 cm (relative minimal difference of 4%) for Rater 4. Significance. Less experienced raters were able to accurately and reliably analyze already captured muscle thickness images of the forearm with low absolute errors.

Refining the FitnessGram with criterion-referenced Standards for Musculoskeletal Fitness

Abstract: In the four decades since the Cooper Institute first developed FitnessGram, research, evaluation, validation, and program enhancement by the Scientific Advisory Board (SAB, https://fitnessgram.net/advisory-board/) have made FitnessGram “the most trusted and widely used fitness assessment, education, and reporting tool in the world” (Plowman et al., 2006; The Cooper Institute, 2022). The sustained commitment by the SAB to science-informed practice including use of criterionreferenced standards based on health outcomes (instead of performance indicators or normative data) has led to refinements in fitness assessments and standards including those for aerobic capacity and body composition (Welk et al., 2011). With the release of the Institute of Medicine’s (IOM) seminal report “Fitness Measures and Health Outcomes in Youth” in 2012, the SAB and The Cooper Institute acknowledged the need to review the FitnessGram musculoskeletal fitness assessments. Specifically, the SAB developed a comprehensive plan to establish and evaluate health-related fitness standards for musculoskeletal fitness. The FitnessGram battery historically included field-based assessments of muscle strength and endurance (i.e., curl-up, push-up, and trunk lift) and flexibility (i.e., back-save sit and reach), but evidence was lacking to support the utility of criterion-referenced health standards for these outcomes. Thus, in this special issue of MPEES, SAB researchers, and colleagues present their findings from a foundational series of studies that aim to fill knowledge gaps related to musculoskeletal fitness assessments in youth. In the first paper, Welk et al. (2022) review and summarize the concepts, approaches, and considerations used by the SAB to explore the development of criterion-referenced standards for musculoskeletal fitness in youth. The authors first outline their conceptual model of health-related fitness and musculoskeletal fitness, with the latter defined as per the IOM as a multidimensional construct encompassing the integrated function of muscle strength, muscle endurance, and muscle power (Institute of Medicine, 2012). The SAB’s model for musculoskeletal fitness guided selection of fitness tests to represent the upper (i.e., grip strength) and lower body (i.e., vertical and long jump) and core (i.e., plank test), with the acknowledgment that one single measure cannot capture this complex construct. As mentioned, criterion-referenced health standards are a foundational and unique element of FitnessGram (Cureton & Warren, 1990; Plowman et al., 2006; Zhu et al., 2011), and the SAB adhered to their established methods when developing standards for musculoskeletal fitness. The process first involves modeling age and sex effects using the Lambda Mu Sigma (LMS) procedures (described in detail elsewhere (Cole, 1990; Cole & Green, 1992)), which are used in three papers in this special issue (Laurson et al., 2022a, 2022b, 2021). Development of LMS curves is followed by receiver operator characteristic (ROC) analyses to identify thresholds for predicting an associated health outcome. Similar to the pioneering approach, the SAB utilized when refining the aerobic fitness and body composition standards, two distinct thresholds were defined with the ROC analyses which permitted categorization of fitness scores into three zones – a healthy zone, a risk zone, and a marginal or intermediary zone. Welk and colleagues outlined other unique considerations of the SAB when setting the musculoskeletal fitness standards including prioritizing indicators directly related to the musculoskeletal system (i.e., bone and muscle health), basing standards on absolute indicators of strength and endurance instead of on measures relative to body weight, and developing standardized protocols for the three primary

Age-Varing Association Between Physical Activity And Health-Related Quality Of Life Among U.S. Adults

Abstract: Several studies have shown a consistently positive association between physical activity (PA) and several domains of health-related quality of life (HRQOL) among older adults, suggesting that promoting PA in the elderly population may affect physical and mental health. However, studies identifying association between PA and HRQOL for all adult age groups are insufficient. PURPOSE: The purposes of this study are to estimate age-associated trends in PA and HRQOL using a separate weighted intercept-only linear time varying effect modeling (TVEM) and to identify the age-varying association between PA and HRQOL using a weighted linear TVEM. METHODS:A total of 5,015 adult samples aged 20-80 years from NHANES (2011-2012) were available for data analysis. PA was calculated as summing weekly minutes of work activity, walk or bicycle activity, recreation activity, and sedentary activity. Four HRQOL variables were based on self-perceived health status. The TVEM was used to analyze the data using R studio and SAS v9.4. The alpha level was set at 05. RESULTS: Overall, estimated PA has decreased with increasing age. PA peaked at age around 23. All HRQOL variables varied by age, except for general health condition variable, which was constant across all ages. Next, there was a significant positive association between PA and general health condition in certain age groups. For people aged 58 to 79, the higher the amount of PA, the better the general health condition. The strongest significant association indicated at age 75 (β = .0003). The significant inverse association between PA and number of days with poor physical health was found. Specifically, the lower the amount of PA among people aged 59-61, the more days they are physically unwell. The strongest significant association indicated at age 60 (β = -.0013). There was no significant association between PA and number of days with poor mental health across all ages. There was a significant negative association between PA and inactive days at the age of 52 to 66. This association peaked at around age 60 (β = -.0011). CONCLUSIONS: While PA steadily declined with age, the significance of the association between PA and HRQOL varied across age groups. Using TVEM, it was able to identify the precise age periods in which certain characteristics were associated with changes in PA and HRQOL variables.

Optimal Frequency Intensity of Physical Activity to Reduce the Risk of Hypertension in the Korean Population

Abstract: PURPOSE: Regular physical activity (PA) is an effective lifestyle modification for preventing hypertension. This study aimed to analyze the optimal frequency of PA required to reduce the incidence of hypertension in the Korean population. Most Korean studies have included only small samples and limited age ranges.METHODS: The present study analyzed 16,299,865 participants aged ≥20 years (44.25±12.74 years) from the 2009 to 2012 Korean National Health Insurance Corporation Survey database. The International Physical Activity Questionnaire was used to assess the frequency and intensity of physical activity. Hazard ratios for incident hypertension were analyzed by physical activity participation, age, and sex using multivariable Cox proportional hazard models, with a non-regular physical activity group as reference.RESULTS: A total of 1,322,674 cases of incident hypertension were identified during the mean follow-up period of over 3 years. Hazard ratios for incident hypertension increased with age, with values of 50.4 and 56.1 for men and women in the older age group, respectively. Hazard ratios for incident hypertension were significantly lower in the regular PA group of middle-aged (4%) and older (7%) adults than in the non-regular PA group. The study revealed that moderate-to-vigorous-intensity PA 3-5 times/week was most effective in reducing the risk of incident hypertension in middle-aged and older adults but not in young adults. We observed no additional lowering of incident hypertension risk in the group undergoing moderate-to-vigorous PA at a frequency of 6-7 days/week compared to the 35 days/week group.CONCLUSIONS: We suggest PA at a frequency of 3-5 times/week for the prevention of incident hypertension in Korean adults.

Objectively Measured Physical Activity Is Lower in Individuals with Normal Weight Obesity in the United States

Abstract: The role of physical activity in normal weight obesity (NWO), which is associated with increased cardiometabolic risk, is not clear. This study aimed to determine body composition phenotype-specific differences in objectively measured physical activity and sedentary time in adults in the United States. A total of 2055 adults with a body mass index (BMI) ≥ 18.5 m2 were studied using 2003–2006 National Health and Nutrition Examination Surveys. Physical activity and percent body fat (BF%) were measured using accelerometer and dual-energy X-ray absorptiometry, respectively. A BF% > 23.1% and >33.3% for men and women, respectively, was considered excess. A BMI of 18.5–24.9 kg/m2 with excess BF% was defined as NWO, while those with normal BF%, as normal weight lean (NWL). A BMI of ≥25 kg/m2 with excess BF% was considered overweight/obesity (OB). Compared to NWL, moderate to vigorous physical activity was significantly lower by 8.3 min (95% confidence interval/CI = −15.20, −1.40) and 10.18 min (95% CI = −14.83, −5.54) per day in NWO and OB, respectively. Low-intensity physical activity was also significantly lower by 17.71 min (95% CI = −30.61, −4.81) per day in NWO compared to NWL. However, sedentary time was not different. Objectively measured physical activity is significantly lower in NWO compared to NWL, while sedentary time is not.