Association between daily step counts and physical activity level among Korean elementary schoolchildren

( Jonghoon Park ),( Kazuko Ishikawa Takata ),( Sangjik Lee ),( Eunkyung Kim ),( Kiwon Lim ),( Hyungryul Kim ),( In Sook Lee ),( Shigeho Tanaka ) 한국운동영양학회 2016 Physical Activity and Nutrition (Phys Act Nutr) Vol.20 No.3

[Purpose] The purpose of the current study was to investigate steps per day (steps/d) and physical activity level (PAL) in Korean elementary school children having normal weight (normal-weight). We also clarified whether a gender difference exited between steps/d and PAL. [Methods] Children aged 9 to 12 y were recruited from two elementary schools located in different urban districts in Korea. The present study included 33 Korean children, of which 18 were normal-weight boys and 15 were normal-weight girls. During the same 1 week study period under free-living conditions the total energy expenditure (TEE) and step counts were estimated using the doubly labeled water (DLW) method and an accelerometer, respectively. We calculated PAL as the TEE/ resting metabolic rate. [Results] The range of PAL was 1.25 - 1.93 with a mean value of 1.57. None of the variables of energy expenditure was significantly different by sex. However, steps/d were significantly higher in boys than in girls. When adjusting regression analysis by gender, steps/ d were positively associated with PAL among all subjects (r = 0.56, P < 0.01). Furthermore, steps/d were positively associated with PAL in boys (r = 0.68, P < 0.01), but not in girls (r = 0.27, P = 0.34). [Conclusion] Our results suggest that locomotive activity may be the main contributor to the individual PAL differences for elementary school boys, while non-locomotive activity may be the main contributor for elementary school girls.

Estimating free-living human energy expenditure

Jonghoon Park,Ishikawa-Takata Kazuko,Eunkyung Kim,Jeonghyun Kim,Jinsook Yoon 한국영양학회 2014 Nutrition Research and Practice Vol.8 No.3

The accuracy and noninvasive nature of the doubly labeled water (DLW) method makes it ideal for the study of human energy metabolism in free-living conditions. However, the DLW method is not always practical in many developing and Asian countries because of the high costs of isotopes and equipment for isotope analysis as well as the expertise required for analysis. This review provides information about the theoretical background and practical aspects of the DLW method, including optimal dose, basic protocols of two- and multiple-point approaches, experimental procedures, and isotopic analysis. We also introduce applications of DLW data, such as determining the equations of estimated energy requirement and validation studies of energy intake.

Validity of the dietary reference intakes for determining energy requirements in older adults

Didace Ndahimana,Na-Young Go,Kazuko Ishikawa-Takata,Jonghoon Park,Eun-Kyung Kim 한국영양학회 2019 Nutrition Research and Practice Vol.13 No.3

BACKGROUND/OBJECTIVES: The objectives of this study were to evaluate the accuracy of the Dietary Reference Intakes (DRI) for estimating the energy requirements of older adults, and to develop and validate new equations for predicting the energy requirements of this population group. MATERIALS/METHODS: The study subjects were 25 men and 23 women with a mean age of 72.2 ± 3.9 years and 70.0 ± 3.3 years, and mean BMI of 24.0 ± 2.1 and 23.9 ± 2.7, respectively. The total energy expenditure (TEE) was measured by using the doubly labeled water (DLW) method, and used to validate the DRI predictive equations for estimated energy requirements (EER) and to develop new EER predictive equations. These developed equations were cross-validated by using the leave-one-out technique. RESULTS: In men, the DRI equation had a -7.2% bias and accurately predicted the EER (meaning EER values within ±10% of the measured TEE) for 64% of the subjects, whereas our developed equation had a bias of -0.1% and an accuracy rate of 84%. In women, the bias was -6.6% for the DRI equation and 0.2% for our developed equation, and the accuracy rate was 74% and 83%, respectively. The predicted EER was strongly correlated with the measured TEE, for both the DRI equations and our developed equations (Pearson’s r = 0.915 and 0.908, respectively). CONCLUSIONS: The DRI equations provided an acceptable prediction of EER in older adults and these study results therefore support the use of these equations in this population group. Our developed equations had a better predictive accuracy than the DRI equations, but more studies need to be performed to assess the performance of these new equations when applied to an independent sample of older adults.

Validation of Dietary Reference Intakes for predicting energy requirements in elementary school-age children

Eun-Kyung Kim,Didace Ndahimana,Kazuko Ishikawa-Takata,Sangjik Lee,Hyungryul Kim,Kiwon Lim,In-Sook Lee,Shigeho Tanaka,Ye-Jin Kim,Yeon-Jung Choi,Mun-Jeong Ju,Jonghoon Park 대한지역사회영양학회 2018 Nutrition Research and Practice Vol.12 No.5

Validation of Dietary Reference Intakes for predicting energy requirements in elementary school-age children

Kim, Eun-Kyung,Ndahimana, Didace,Ishikawa-Takata, Kazuko,Lee, Sangjik,Kim, Hyungryul,Lim, Kiwon,Lee, In-Sook,Tanaka, Shigeho,Kim, Ye-Jin,Choi, Yeon-Jung,Ju, Mun-Jeong,Park, Jonghoon The Korean Nutrition Society 2018 Nutrition Research and Practice Vol.12 No.4

BACKGROUND/OBJECTIVES: Dietary Reference Intakes (DRI) for energy are derived from total energy expenditure (TEE) measured using the doubly labelled water (DLW) method. The objective of this study was to assess the validity of DRI for predicting the energy requirements of elementary school-age children. SUBJECTS/METHODS: The present study involved 25 elementary school-age children aged between 9 and 11 years. TEE was assessed by the DLW method, and the results were compared with the TEE predicted by the DRI equations in order to evaluate accuracy. RESULTS: The subjects' TEE measured by the DLW method was $1,925.2{\pm}380.9kcal/day$ in boys and $1,930.0{\pm}279.4kcal/day$ in girls, whereas resting energy expenditure was $1,220.2{\pm}176.9kcal/day$ in boys and $1,245.9{\pm}171.3kcal/day$ for girls. The physical activity level was $1.58{\pm}0.20$ in boys and $1.55{\pm}0.13$ in girls. The mean bias between the predicted and measured TEE was 12.6% in boys and -1.6% in girls, and the percentage of accurate predictions was 28.6% and 63.6%, respectively. In boys, the equation resulted in underprediction of TEE among the subjects having low TEE values, whereas there was overprediction among subjects having high TEE values as shown by the Bland-Altman plot. On the contrary, this proportional bias was not observed in girls. CONCLUSIONS: The findings of this study suggest that the DRI equation for energy could result in the overestimation of energy requirements in elementary school-age boys. In the case of girls, the equations could be accurate at the group level. However, the DRI appears to be invalid for individual girls, as more than one third of girls had their TEE inaccurately predicted. We recommend more studies for confirmation of these results.

Validation of Dietary Reference Intakes for predicting energy requirements in elementary school-age children

Eun-Kyung Kim,Didace Ndahimana,Kazuko Ishikawa-Takata,Sangjik Lee,Hyungryul Kim,Kiwon Lim,In-Sook Lee,Shigeho Tanaka,Ye-Jin Kim,Yeon-Jung Choi,Mun-Jeong Ju,Jonghoon Park 대한지역사회영양학회 2018 Nutrition Research and Practice Vol.12 No.4

BACKGROUND/OBJECTIVES: Dietary Reference Intakes (DRI) for energy are derived from total energy expenditure (TEE) measured using the doubly labelled water (DLW) method. The objective of this study was to assess the validity of DRI for predicting the energy requirements of elementary school-age children. SUBJECTS/METHODS: The present study involved 25 elementary school-age children aged between 9 and 11 years. TEE was assessed by the DLW method, and the results were compared with the TEE predicted by the DRI equations in order to evaluate accuracy. RESULTS: The subjects’ TEE measured by the DLW method was 1,925.2 ± 380.9 kcal/day in boys and 1,930.0 ± 279.4 kcal/day in girls, whereas resting energy expenditure was 1,220.2 ± 176.9 kcal/day in boys and 1,245.9 ± 171.3 kcal/day for girls. The physical activity level was 1.58 ± 0.20 in boys and 1.55 ± 0.13 in girls. The mean bias between the predicted and measured TEE was 12.6% in boys and -1.6% in girls, and the percentage of accurate predictions was 28.6% and 63.6%, respectively. In boys, the equation resulted in underprediction of TEE among the subjects having low TEE values, whereas there was overprediction among subjects having high TEE values as shown by the Bland-Altman plot. On the contrary, this proportional bias was not observed in girls. CONCLUSIONS: The findings of this study suggest that the DRI equation for energy could result in the overestimation of energy requirements in elementary school-age boys. In the case of girls, the equations could be accurate at the group level. However, the DRI appears to be invalid for individual girls, as more than one third of girls had their TEE inaccurately predicted. We recommend more studies for confirmation of these results.

Validity of the dietary reference intakes for determining energy requirements in older adults

Ndahimana, Didace,Go, Na-Young,Ishikawa-Takata, Kazuko,Park, Jonghoon,Kim, Eun-Kyung The Korean Nutrition Society 2019 Nutrition Research and Practice Vol.13 No.3

BACKGROUND/OBJECTIVES: The objectives of this study were to evaluate the accuracy of the Dietary Reference Intakes (DRI) for estimating the energy requirements of older adults, and to develop and validate new equations for predicting the energy requirements of this population group. MATERIALS/METHODS: The study subjects were 25 men and 23 women with a mean age of $72.2{\pm}3.9\;years$ and $70.0{\pm}3.3\;years$, and mean BMI of $24.0{\pm}2.1$ and $23.9{\pm}2.7$, respectively. The total energy expenditure (TEE) was measured by using the doubly labeled water (DLW) method, and used to validate the DRI predictive equations for estimated energy requirements (EER) and to develop new EER predictive equations. These developed equations were cross-validated by using the leave-one-out technique. RESULTS: In men, the DRI equation had a -7.2% bias and accurately predicted the EER (meaning EER values within ${\pm}10%$ of the measured TEE) for 64% of the subjects, whereas our developed equation had a bias of -0.1% and an accuracy rate of 84%. In women, the bias was -6.6% for the DRI equation and 0.2% for our developed equation, and the accuracy rate was 74% and 83%, respectively. The predicted EER was strongly correlated with the measured TEE, for both the DRI equations and our developed equations (Pearson's r = 0.915 and 0.908, respectively). CONCLUSIONS: The DRI equations provided an acceptable prediction of EER in older adults and these study results therefore support the use of these equations in this population group. Our developed equations had a better predictive accuracy than the DRI equations, but more studies need to be performed to assess the performance of these new equations when applied to an independent sample of older adults.

The association of locomotive and non-locomotive physical activity measured by an accelerometer with functional fitness in healthy elderly men: a pilot study

( Hyejoon Park ),( Wonil Park ),( Moran Lee ),( Nayoung Ko ),( Eunkyung Kim ),( Kazuko Ishikawa-takata ),( Jonghoon Park ) 한국운동영양학회 2018 Physical Activity and Nutrition (Phys Act Nutr) Vol.22 No.1

[Purpose] The purpose of this study was to investigate the relationship of various aspects of daily physical activity, such as the number of steps, time spent in moderate to vigorous intensity physical activity (MVPA), and locomotive and non-locomotive MVPA measured by a triaxial accelerometer, with the functional fitness in healthy elderly men. [Methods] The subjects of this study were 22 healthy elderly men aged over 65 years. The participants wore a triaxial accelerometer for two weeks to estimate their daily physical activities. The level of functional fitness was measured based on "National Fitness Award 100 in Korea" immediately after the measurement of two weeks of daily physical activities. [Results] The results showed that active healthy elderly men with more than 6,500 walking steps per day and more than 60 min per day spent in MVPA showed a significantly higher 2-min marching in place and index of cardiorespiratory endurance compared to less physically active participants. Particularly, locomotive MVPA was significantly associated with cardiorespiratory endurance levels (r = 0.50), whereas non-locomotive MVPA was not associated with other measurements of functional fitness. [Conclusion] Increased MVPA time, especially the locomotive MVPA, can effectively suppress the decrease in cardiorespiratory endurance level in elderly men. However, no association was observed between non-locomotive MVPA, such as household activities, and functional fitness in healthy elderly men.

한국 성인과 노인을 대상으로 이중표식수법을 이용한 신체활동분류표 타당도 평가

한혜지(Hye-Ji Han),전하연(Ha-Yeon Jun),박종훈(Jonghoon Park),Kazuko Ishikawa-Takata,김은경(Eun-Kyung Kim) 한국영양학회 2023 Journal of Nutrition and Health Vol.56 No.4

그동안 국내 연구에서 PAL을 산출하기 위해 사용해온 18단계 신체활동분류표로 신체활동을 평가하는 데 한계가 있었기에 새롭게 한국인을 위한 신체활동분류표가 보고되었다. 이에 본 연구에서 총에너지소비량을 측정하는 gold standard인 이중표식수법을 이용하여 새로 보고된 신체활동분류표의 타당도를 평가한 결과, TEE<SUB>DLW</SUB>와 TEE<SUB>PACT</SUB> 간의 유의한 차이가 없었으며 TEE<SUB>DLW</SUB>와 TEE<SUB>PACT</SUB> 간의 스피어만 상관관계 (r = 0.769)는 유의한 높은 양의 상관성을 보였다. 즉, 본 연구에서 TEE 및 PAL 산출을 위해 새로운 신체활동분류표의 사용이 타당한 것으로 평가되었으며, 앞으로 이와 관련된 연구 결과는 2025 한국인 영양소 섭취기준에서 에너지필요 추정량 산출식에 필요한 신체활동단계별 계수 (PA)를 결정하는데 유용한 자료가 될 것으로 기대된다. 또한 개인별 및 연구 목적으로도 쉽게 사용하기 위해서, 신체활동분류표를 이용한 웹 버전의 소프트웨어 프로그램 및 스마트폰 어플리케이션의 개발이 필요하다. Purpose: This study evaluated the validity of a physical activity classification table (PACT) based on total energy expenditure (TEE) and physical activity level (PAL) measured using the doubly labeled water (DLW) method in Korean adults and the elderly. Methods: A total of 141 (male 70, female 71) adults and elderly were included. The reference standards TEE<SUB>DLW</SUB>, PAL<SUB>DLW</SUB> were measured over a 14-day period using DLW. A 24-hour physical activity diary was kept for three days (two days during the week and one day on the weekend). PAL<SUB>PACT</SUB> was calculated by classifying the activity type and intensity using the PACT. PAL<SUB>PACT</SUB> was multiplied by resting energy expenditure measured by indirect calorimetry to estimate TEE<SUB>PACT</SUB>. Results: The mean age of the study participants was 50.5 ± 18.8 years, and the mean body mass index was 23.4 ± 3.3 kg/m2. A comparison of TEE<SUB>DLW</SUB> and TEE<SUB>PACT</SUB> by sex and age showed no significant differences. The bias, the difference between TEE<SUB>DLW</SUB> and TEE<SUB>PACT</SUB>, was male 17.3 kcal/day and female −4.5 kcal/day. The percentage of accurate predictions (values within ± 10% of the TEE<SUB>DLW</SUB>) of TEE<SUB>PACT</SUB> was 58.6% in males and 54.9% in females, with the highest prediction values in the age group 40–64 years (70.9%) in males and over 65 years (73.9%) in females. The spearman correlation coefficient (r) between TEE<SUB>PACT</SUB> and TEE<SUB>DLW</SUB> was 0.769, indicating a significant positive correlation (p < 0.001). Conclusion: In this study, the use of a new PACT for calculating TEE and PAL was evaluated as valid. A web version of the software program and a smartphone application need to be developed using PACT to make it easier to apply for research purposes.

An academic cooperation between the Japan Sports Nutrition Association (JSNA) and the Korean Society for Exercise Nutrition (KSEN)

Masaharu Kagawa,Yosuke Nagashima,Satomi Oshima,Akiko Sato,Tatsuya Ishizu,Kazuko Ishikawa-Takata,Motoko Taguchi 한국운동영양학회 2024 Physical Activity and Nutrition (Phys Act Nutr) Vol.28 No.2

[Purpose] The Japan Sports Nutrition Association (JSNA) is an academic society that aims to contribute to people’s health and the development of sports in Japan. [Methods] After numerous communication and academic events, the JSNA and the Korean Society for Exercise Nutrition (KSEN) exchanged a Memorandum of Understanding (MoU) in 2018. [Results] Based on the MoU, the JSNA and KSEN organized academic exchange events until the Coronavirus Disease 2019 pandemic and subsequent travel restrictions and lockdowns. [Conclusion] After four years of the pandemic and the downgrading of Coronavirus Disease 2019 infection risk, it is hoped that academic exchanges between the societies will resume gradually and enhance members’ recognition of the cooperation between the JSNA and KSEN for active collaborations in the future.