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Potter AW, Looney DP, Tharion WJ, Nindl LJ, Pazmino A, Soto LD, Arcidiacono DM, Friedl KE. Physical performance and body composition reference values for modern US Marine Corps women. BMJ Nutr Prev Health 2023; 6:234-242. [PMID: 38618530 PMCID: PMC11009549 DOI: 10.1136/bmjnph-2023-000757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 10/13/2023] [Indexed: 04/16/2024] Open
Abstract
Women's roles in the US military have progressively changed over the past several decades. Previously women were barred from combat roles. Recent change in policy allow women into combat roles in the Marine Corps, and this has led to women being trained for combat specialties. Objectives This observational cross-sectional study describes body composition and performance values for modern Marine Corps women. Methods Volunteers were 736 Marine women who were assessed for body composition and physical performance; (age 29.5±7.3 (18-56) years; height 163.6±6.8 (131.0-186.1) cm; body mass 68.3±9.2 (42.0-105.3) kg; years in the military 8.9±6.8 (0.5-37) years-in-service). Body composition measures were obtained using dual-energy X-ray absorptiometry and single-frequency bioelectrical impedance analyses. Performance measures were obtained from official physical and combat fitness test scores (PFT; CFT) as well as from data on measured countermovement jumps (CMJ) on a calibrated force platform. Results Mean body composition metrics for Marine women were: 47.5±5.7 fat free mass (FFM) (kg), 30.1%±6.4% body fat (%BF), 2.6±0.3 bone mineral content (kg), and 25.5±2.8 body mass index (kg/m2); performance metrics included 43.4±3.2 maximal oxygen uptake (VO2max; mL.kg.min), 22.4±7.1 CMJ height (cm) and 2575±565.2 CMJ peak power (W). Data showed strong correlations (r) (≥0.70) between PFT and VO2max scores (0.75), and moderate correlations (≥0.50) between CFT and VO2max scores (0.57), CFT and PFT scores (0.60), FFM and CMJ peak power (W) (0.68), and %BF to VO2max (-0.52), PFT (-0.54), CMJ-Ht (-0.52) and CMJ relative power (W/kg) (-0.54). Conclusion Modern Marine women are both lean and physically high performing. Body composition is a poor predictor of general physical performance.
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Affiliation(s)
- Adam W Potter
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
| | - David P Looney
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
| | - William J Tharion
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
| | - Lyndsey J Nindl
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, Tennessee, USA
| | - Angie Pazmino
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
| | - Lara D Soto
- Thermal and Mountain Medicine Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
| | - Danielle M Arcidiacono
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, Tennessee, USA
| | - Karl E Friedl
- Office of the Senior Scientist, US Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA
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Foulis SA, Hughes JM, Spiering BA, Walker LA, Guerriere KI, Taylor KM, Proctor SP, Friedl KE. US Army basic combat training alters the relationship between body mass index and per cent body fat. BMJ Mil Health 2023; 169:340-345. [PMID: 34413114 PMCID: PMC10423487 DOI: 10.1136/bmjmilitary-2021-001936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/03/2021] [Indexed: 11/04/2022]
Abstract
INTRODUCTION/BACKGROUND As a proxy for adiposity, body mass index (BMI) provides a practical public health metric to counter obesity-related disease trends. On an individual basis, BMI cannot distinguish fat and lean components of body composition. Further, the relationship between BMI and body composition may be altered in response to physical training. We investigated this dynamic relationship by examining the effect of US Army basic combat training (BCT) on the association between BMI and per cent body fat (%BF). METHODS BMI and %BF were measured at the beginning (week 1) and end (week 9) of BCT in female (n=504) and male (n=965) trainees. Height and weight were obtained for BMI, and body composition was obtained by dual X-ray absorptiometry. Sensitivity and specificity of BMI-based classification were determined at two BMI thresholds (25 kg/m2 and 27.5 kg/m2). RESULTS A progressive age-related increase in fat-free mass index (FFMI) was observed, with an inflection point at age 21 years. In soldiers aged 21+, BMI of 25.0 kg/m2 predicted 33% and 29% BF in women and 23% and 20% BF in men and BMI of 27.5 kg/m2 predicted 35% and 31% BF in women and 26% and 22% BF in men, at the start and end of BCT, respectively. Sensitivity and specificity of BMI-based classification of %BF were poor. Soldiers below BMI of 20 kg/m2 had normal instead of markedly reduced %BF, reflecting especially low FFMI. CONCLUSIONS BCT alters the BMI-%BF relationship, with lower %BF at a given BMI by the end of BCT compared with the beginning, highlighting the unreliability of BMI to try to estimate body composition. The specific BMI threshold of 25.0 kg/m2, defined as 'overweight', is an out-of-date metric for health and performance outcomes. To the extent that %BF reflects physical readiness, these data provide evidence of a fit and capable military force at BMI greater than 25.0 kg/m2.
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Dyches KD, Friedl KE, Greeves JP, Keller MF, McClung HL, McGurk MS, Popp KL, Teyhen DS. Physiology of Health and Performance: Enabling Success of Women in Combat Arms Roles. Mil Med 2023; 188:19-31. [PMID: 37490562 DOI: 10.1093/milmed/usac256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 02/28/2022] [Accepted: 08/16/2022] [Indexed: 07/27/2023] Open
Abstract
INTRODUCTION The modern female soldier has yet to be fully characterized as she steps up to fill new combat roles that have only recently been opened to women. Both U.S. and U.K. military operational research efforts are supporting a science-based evolution of physical training and standards for female warfighters. The increasing representation of women in all military occupations makes it possible to discover and document the limits of female physiological performance. METHOD An informal Delphi process was used to synthesize an integrated concept of current military female physiological research priorities and emerging findings using a panel of subject matter experts who presented their research and perspectives during the second Women in Combat Summit hosted by the TriService Nursing Research Program in February 2021. RESULTS The physical characteristics of the modern soldier are changing as women train for nontraditional military roles, and they are emerging as stronger and leaner. Capabilities and physique will likely continue to evolve in response to new Army standards and training programs designed around science-based sex-neutral requirements. Strong bones may be a feature of the female pioneers who successfully complete training and secure roles traditionally reserved for men. Injury risk can be reduced by smarter, targeted training and with attention directed to female-specific hormonal status, biomechanics, and musculoskeletal architecture. An "estrogen advantage" appears to metabolically support enhanced mental endurance in physically demanding high-stress field conditions; a healthy estrogen environment is also essential for musculoskeletal health. The performance of female soldiers can be further enhanced by attention to equipment that serves their needs with seemingly simple solutions such as a suitable sports bra and personal protective equipment that accommodates the female anatomy. CONCLUSIONS Female physiological limits and performance have yet to be adequately defined as women move into new roles that were previously developed and reserved for men. Emerging evidence indicates much greater physical capacity and physiological resilience than previously postulated.
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Affiliation(s)
- Karmon D Dyches
- Military Operational Medicine Research Program, U.S. Army Medical Research and Development Command, Fort Detrick, MD 21702, USA
| | - Karl E Friedl
- Biophysics and Biomedical Modeling Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760, USA
| | - Julie P Greeves
- Department of Army Health and Performance Research (AHPR), British Army, Andover, Hampshire SP11 8HT, UK
| | - Margaux F Keller
- Henry M Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD 20817, USA
| | - Holly L McClung
- Biophysics and Biomedical Modeling Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760, USA
| | - Michael S McGurk
- Research and Analysis Directorate, U.S. Army Center for Initial Military Training, Fort Eustis, VA 23604, USA
| | - Kristin L Popp
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760, USA
| | - Deydre S Teyhen
- Chief, U.S. Army Medical Specialist Corps, U.S. Army Medical Command, Falls Church, VA 22042, USA
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Lavoie EM, Holden LD, Vangala SV, Santee WR, Pryor RR, Friedl KE, Potter AW, Looney DP. Effects of modern military footwear on the oxygen costs of walking in US Army personnel. FOOTWEAR SCIENCE 2023. [DOI: 10.1080/19424280.2022.2164622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Elizabeth M. Lavoie
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN, USA
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, NY, USA
| | - Lucas D. Holden
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
- Oak Ridge Institute for Science and Education (ORISE), Oak Ridge, TN, USA
| | - Sai V. Vangala
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - William R. Santee
- United States Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Riana R. Pryor
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, NY, USA
| | - Karl E. Friedl
- Chief Physiologist of the Army, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Adam W. Potter
- Thermal and Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - David P. Looney
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, USA
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Harty PS, Friedl KE, Nindl BC, Harry JR, Vellers HL, Tinsley GM. Military Body Composition Standards and Physical Performance: Historical Perspectives and Future Directions. J Strength Cond Res 2022; 36:3551-3561. [PMID: 34593729 DOI: 10.1519/jsc.0000000000004142] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
ABSTRACT Harty, PS, Friedl, KE, Nindl, BC, Harry, JR, Vellers, HL, and Tinsley, GM. Military body composition standards and physical performance: historical perspectives and future directions. J Strength Cond Res 36(12): 3551-3561, 2022-US military physique and body composition standards have been formally used for more than 100 years. These metrics promote appropriate physical fitness, trim appearance, and long-term health habits in soldiers, although many specific aspects of these standards have evolved as evidence-based changes have emerged. Body composition variables have been shown to be related to many physical performance outcomes including aerobic capacity, muscular endurance, strength and power production, and specialized occupational tasks involving heavy lifting and load carriage. Although all these attributes are relevant, individuals seeking to improve military performance should consider emphasizing strength, hypertrophy, and power production as primary training goals, as these traits appear vital to success in the new Army Combat Fitness Test introduced in 2020. This fundamental change in physical training may require an adjustment in body composition standards and methods of measurement as physique changes in modern male and female soldiers. Current research in the field of digital anthropometry (i.e., 3-D body scanning) has the potential to dramatically improve performance prediction algorithms and potentially could be used to inform training interventions. Similarly, height-adjusted body composition metrics such as fat-free mass index might serve to identify normal weight personnel with inadequate muscle mass, allowing for effective targeted nutritional and training interventions. This review provides an overview of the origin and evolution of current US military body composition standards in relation to military physical readiness, summarizes current evidence relating body composition parameters to aspects of physical performance, and discusses issues relevant to the emerging modern male and female warrior.
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Affiliation(s)
- Patrick S Harty
- Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, Texas
| | - Karl E Friedl
- U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts; and
| | - Bradley C Nindl
- Department of Sports Medicine and Nutrition, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - John R Harry
- Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, Texas
| | - Heather L Vellers
- Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, Texas
| | - Grant M Tinsley
- Department of Kinesiology & Sport Management, Texas Tech University, Lubbock, Texas
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Stojković M, Heinrich KM, Čvorović A, Jeknić V, Greco G, Kukić F. Accuracy of Body Mass Index and Obesity Status in Police Trainees. Eur J Investig Health Psychol Educ 2022; 12:42-49. [PMID: 35049533 PMCID: PMC8775040 DOI: 10.3390/ejihpe12010004] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 12/30/2021] [Accepted: 01/07/2022] [Indexed: 02/05/2023] Open
Abstract
The first aim of this study was to compare body mass index (BMI) (indirect method) classification with the body fat percent (PBF) (direct method) and to determine how BMI classifies subjects with different levels of skeletal muscle mass percent (PSMM). The second aim was to determine the prevalence of overweight and obesity status among police trainees (PTs). A total of 103 male PTs participated in this research: age = 21.46 ± 0.64 years, body mass (BM) = 75.97 ± 8.10 kg, body height (BH) = 174.07 ± 6.31 cm, BMI = 25.05 ± 2.12 kg/m2. The InBody 370 multichannel bioelectrical impedance analysis (BIA) measured body composition. Study results indicated that muscular PTs could be misclassified as overweight and that PBF identified more subjects as obese. Namely, three PTs were obese according to BMI, while 13 were obese according to PBF. The information provided by this research could be used to help professionals understand the importance of measuring body composition, and the inaccuracies in BMI classification. In conclusion, whenever possible PSMM and PBF should replace the utilization of BMI to screen overweight and obesity in PTs. Agencies may think of using BIA as non-invasive, quick and inexpensive measurement tool.
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Affiliation(s)
- Miloš Stojković
- Faculty of Sport and Physical Education, University of Belgrade, 1040 Belgrade, Serbia; (M.S.); (V.J.)
| | - Katie M. Heinrich
- Department of Kinesiology, Kansas State University, Manhattan, KS 66502, USA;
| | - Aleksandar Čvorović
- Police Sports Education Center, Abu Dhabi Police, Abu Dhabi 253, United Arab Emirates; (A.Č.); (F.K.)
| | - Velimir Jeknić
- Faculty of Sport and Physical Education, University of Belgrade, 1040 Belgrade, Serbia; (M.S.); (V.J.)
| | - Gianpiero Greco
- Department of Basic Medical Sciences, Neuroscience and Sense Organs, University of Study of Bari, 70121 Bari, Italy
- Correspondence:
| | - Filip Kukić
- Police Sports Education Center, Abu Dhabi Police, Abu Dhabi 253, United Arab Emirates; (A.Č.); (F.K.)
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Naimo MA, Varanoske AN, Hughes JM, Pasiakos SM. Skeletal Muscle Quality: A Biomarker for Assessing Physical Performance Capabilities in Young Populations. Front Physiol 2021; 12:706699. [PMID: 34421645 PMCID: PMC8376973 DOI: 10.3389/fphys.2021.706699] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/09/2021] [Indexed: 12/28/2022] Open
Abstract
Muscle quality (MQ), defined as the amount of strength and/or power per unit of muscle mass, is a novel index of functional capacity that is increasingly relied upon as a critical biomarker of muscle health in low functioning aging and pathophysiological adult populations. Understanding the phenotypical attributes of MQ and how to use it as an assessment tool to explore the efficacy of resistance exercise training interventions that prioritize functional enhancement over increases in muscle size may have implications for populations beyond compromised adults, including healthy young adults who routinely perform physically demanding tasks for competitive or occupational purposes. However, MQ has received far less attention in healthy young populations than it has in compromised adults. Researchers and practitioners continue to rely upon static measures of lean mass or isolated measures of strength and power, rather than using MQ, to assess integrated functional responses to resistance exercise training and physical stress. Therefore, this review will critically examine MQ and the evidence base to establish this metric as a practical and important biomarker for functional capacity and performance in healthy, young populations. Interventions that enhance MQ, such as high-intensity stretch shortening contraction resistance exercise training, will be highlighted. Finally, we will explore the potential to leverage MQ as a practical assessment tool to evaluate function and enhance performance in young populations in non-traditional research settings.
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Affiliation(s)
- Marshall A Naimo
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, United States
| | - Alyssa N Varanoske
- Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA, United States.,Oak Ridge Institute for Science and Education, Oak Ridge, TN, United States
| | - Julie M Hughes
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, MA, United States
| | - Stefan M Pasiakos
- Military Nutrition Division, United States Army Research Institute of Environmental Medicine, Natick, MA, United States
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Looney DP, Doughty EM, Figueiredo PS, Vangala SV, Pryor JL, Santee WR, McClung HL, Potter AW. Effects of modern military backpack loads on walking speed and cardiometabolic responses of US Army Soldiers. APPLIED ERGONOMICS 2021; 94:103395. [PMID: 33652153 DOI: 10.1016/j.apergo.2021.103395] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 02/12/2021] [Accepted: 02/17/2021] [Indexed: 06/12/2023]
Abstract
INTRODUCTION Military leaders must understand how modern military equipment loads affect trade-offs between movement speed and physiological strain to optimize pacing strategies. PURPOSE To evaluate the effects of load carried in a recently developed military backpack on the walking speed and cardiometabolic responses of dismounted warfighters. METHODS Fifteen soldiers (1 woman, 14 men; age, 22 ± 2 years; height, 173 ± 7 cm; body mass (BM), 73 ± 10 kg) completed incremental walking tests with four external load conditions (0, 22, 44, or 66% BM) using the US Army's newest backpack: the Modular Lightweight Load-Carrying Equipment 4000 (MOLLE 4000). Oxygen uptake (V̇O2) and heart rate (HR) were evaluated relative to maximal values (V̇O2max and HRmax respectively). Testing ceased when participants completed the highest tested speed (1.97 m s-1), exceeded a respiratory exchange ratio (RER) of 1.00, or reached volitional exhaustion. RESULTS Peak speed significantly decreased (p < 0.03) with successively heavier loads (0% BM, 1.95 ± 0.06 m s-1; 22% BM, 1.87 ± 0.10 m s-1; 44% BM, 1.69 ± 0.13 m s-1; 66% BM, 1.48 ± 0.13 m s-1). Peak V̇O2 was significantly lower (p < 0.01) with 0% BM (47 ± 5% V̇O2max) than each load (22% BM, 58 ± 8% V̇O2max; 44% BM, 63 ± 10% V̇O2max; 66% BM, 61 ± 11% V̇O2max). Peak HR was significantly lower (p < 0.01) with 0% BM (71 ± 5% HRmax) versus each load (22% BM, 83 ± 6% HRmax; 44% BM, 87 ± 6% HRmax; 66% BM, 88 ± 6% HRmax). CONCLUSION Overburdened warfighters suffer severe impairments in walking speed even when carrying recently developed military load carriage equipment. Our results suggest that the relative work intensity of heavy load carriage may be better described when expressed relative to HRmax versus V̇O2max.
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Affiliation(s)
- David P Looney
- US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Natick, MA, 01760, USA
| | - Elizabeth M Doughty
- US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Natick, MA, 01760, USA; Oak Ridge Institute for Science and Education (ORISE), 1299 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Peter S Figueiredo
- US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Natick, MA, 01760, USA; Oak Ridge Institute for Science and Education (ORISE), 1299 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Sai V Vangala
- US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Natick, MA, 01760, USA; Oak Ridge Institute for Science and Education (ORISE), 1299 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - J Luke Pryor
- Center for Research and Education in Special Environments, Department of Exercise and Nutrition Sciences, University at Buffalo, NY, 14214, USA
| | - William R Santee
- US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Natick, MA, 01760, USA; Oak Ridge Institute for Science and Education (ORISE), 1299 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Holly L McClung
- US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Natick, MA, 01760, USA
| | - Adam W Potter
- US Army Research Institute of Environmental Medicine (USARIEM), 10 General Greene Avenue, Natick, MA, 01760, USA.
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Böswald LF, Wenderlein J, Straubinger RK, Ulrich S, Kienzle E. Processing Matters in Nutrient-Matched Laboratory Diets for Mice-Energy and Nutrient Digestibility. Animals (Basel) 2021; 11:523. [PMID: 33671449 PMCID: PMC7922409 DOI: 10.3390/ani11020523] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 02/10/2021] [Accepted: 02/13/2021] [Indexed: 01/27/2023] Open
Abstract
Starch gelatinization is a major determinant of carbohydrate digestibility and varies with diet processing. Laboratory rodent diets are often marketed as identical, but are sold in different forms, regardless of the markedly higher starch gelatinization in extruded than in pelleted diets. Our hypothesis was that this would impact energy and nutrient digestibility in mice fed pellets or extrudate, respectively. Trial 1 showed that feeding C57BL/6 mice a standard maintenance diet in extruded form results in a significantly higher digestibility of organic matter, energy, and carbohydrates than the identical diet in pelleted form. The replication of the experiment, however, revealed a variation between batches of the same pelleted diet regarding starch and total dietary fiber contents. Given the significant differences in diet digestibility and the potential impacts of digestibility on nutrient utilization, the intestinal microbiome, and intermediary metabolism, trials performed with differently processed diets are not comparable. This might partly explain failures to reproduce results, especially in gastrointestinal or microbiome research. Considering this impact on experimental animals, the degree of starch gelatinization should be declared in the diet information for laboratory animal diets. The differences between batches of laboratory animal diets as observed in the pellets are not acceptable.
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Affiliation(s)
- Linda F. Böswald
- Chair for Animal Nutrition and Dietetics, Ludwig-Maximilians-Universität München, 85764 Oberschleißheim, Germany;
| | - Jasmin Wenderlein
- Institute for Infectious Diseases, Ludwig-Maximilians-Universität München, 80539 Munich, Germany; (J.W.); (R.K.S.); (S.U.)
| | - Reinhard K. Straubinger
- Institute for Infectious Diseases, Ludwig-Maximilians-Universität München, 80539 Munich, Germany; (J.W.); (R.K.S.); (S.U.)
| | - Sebastian Ulrich
- Institute for Infectious Diseases, Ludwig-Maximilians-Universität München, 80539 Munich, Germany; (J.W.); (R.K.S.); (S.U.)
| | - Ellen Kienzle
- Chair for Animal Nutrition and Dietetics, Ludwig-Maximilians-Universität München, 85764 Oberschleißheim, Germany;
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Tian Q, Wang H, Kaudimba KK, Guo S, Zhang H, Gao S, Wang R, Luan X, Lee JKW, Chen P, Liu T, Wang R. Characteristics of Physical Fitness and Cardiometabolic Risk in Chinese University Students with Normal-Weight Obesity: A Cross-Sectional Study. Diabetes Metab Syndr Obes 2020; 13:4157-4167. [PMID: 33177856 PMCID: PMC7649220 DOI: 10.2147/dmso.s280350] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 10/14/2020] [Indexed: 12/14/2022] Open
Abstract
PURPOSE To (i) describe the characteristics of physical fitness and cardiometabolic risk in Chinese university students with normal-weight obesity (NWO); (ii) assess the association between NWO with physical fitness and cardiometabolic risk. METHODS A total of 249 participants from the 2018 Shanghai University of Sport Alumni Health Cohort Study in China formed the study cohort. NWO was defined as normal body mass index (17.9-23.9 kg/m2 for males; 17.2-23.9 kg/m2 for females) but with excess body-fat percentage (≥20% for males; ≥30% for females). Body composition was assessed by dual-energy X-ray absorptiometry. Physical-fitness scores were calculated from a battery of sex-specific tests. Cardiometabolic risk was calculated using a continuous clustered risk (MetS) score. RESULTS We found that 16.7% of male and 45.3% of female university students were classified as having NWO. Participants with NWO showed worse cardiorespiratory fitness than those with normal weight (NW) (male NWO (37±8) vs male NW (41±6) mL/kg/min, p<0.01; female NWO (31±4) vs female NW (33±6) mL/kg/min, p<0.01). NWO was associated negatively with the fitness score (OR = 0.853; 95% CI = 0.793-0.917) and was associated positively with the MetS score (1.280; 1.162-1.410). CONCLUSION University students with NWO were characterized by higher cardiometabolic risk and lower levels of physical fitness. Our findings implied that university students with NWO should be mindful of the potential hidden health risks of excess body fat and participate in exercise to enhance physical fitness.
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Affiliation(s)
- Qianqian Tian
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
| | - Hui Wang
- State Key Laboratory of Genetic Engineering, Department of Endocrinology and Metabolism, Institute of Metabolism and Integrative Biology, Human Phenome Institute, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, People’s Republic of China
| | | | - Shanshan Guo
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
| | - Haixin Zhang
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
| | - Song Gao
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
| | - Ruwen Wang
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
| | - Xin Luan
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
| | - Jason Kai Wei Lee
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Global Asia Institute, National University of Singapore, Singapore
- N.1 Institute for Health, National University of Singapore, Singapore
| | - Peijie Chen
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
| | - Tiemin Liu
- State Key Laboratory of Genetic Engineering, Department of Endocrinology and Metabolism, Institute of Metabolism and Integrative Biology, Human Phenome Institute, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, People’s Republic of China
- Correspondence: Tiemin Liu State Key Laboratory of Genetic Engineering, Department of Endocrinology and Metabolism, Institute of Metabolism and Integrative Biology, Human Phenome Institute, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, People’s Republic of ChinaTel/Fax +86-21- 31246765 Email
| | - Ru Wang
- School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of China
- Ru Wang School of Kinesiology, Shanghai University of Sport, Shanghai, People’s Republic of ChinaTel/Fax +86-21-65507351 Email
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