Correlating mechanical work with energy consumption during gait throughout pregnancy
Tóm tắt
Measures of mechanical work may be useful in evaluating efficiency of walking during pregnancy. Various adaptations in the body during pregnancy lead to altered gait, consequently contributing to the total energy cost of walking. Measures of metabolic energy expenditure may not be reliable for measuring energetic cost of gait during pregnancy as pregnancy results in numerous metabolic changes resulting from foetal development. Therefore, the aim of this study is to determine if mechanical work prediction equations correlate with the metabolic energy cost of gait during pregnancy. Thirty-five (35) women (27.5 ± 6.1 years) gave informed consent for participation in the study at different weeks of gestation pregnancy. Gas exchange and gait data were recorded while walking at a fixed self-selected walking speed. External (Wext) work was estimated assuming no energy transfer between segments, while internal work (Wint) assumed energy transfer between segments. Hence total energy of the body (Wtot) was calculated based on the segmental changes relative to the surrounding, and relative to the centre of mass of the whole body. Equations for mechanical work were correlated with net and gross O2 rate, and O2 cost. External, internal and total mechanical energy showed significant positive relationship with gross O2 rate (r = 0.48, r = 0.35; and r = 0.49 respectively), and gross O2 cost (r = 0.42; r = 0.70, and r = 0.62, respectively). In contrast, external, internal and total mechanical energy had no significant relationship with net O2 rate (r = 0.19, r = 0.24, and r = 0.24, respectively). Net O2 cost was significant related Wext (r = 0.49) Wint (r = 0.66) and Wtot (r = 0.62). Energy recovery improved with increase in gait speed. Measures of mechanical work, when adjusted for resting energy expenditure, and walking speed may be useful in comparing metabolic energy consumption between women during pregnancy, or assessment or gait changes of the same individual throughout pregnancy.
Tài liệu tham khảo
Byrne NM, Groves AM, McIntyre HD, Callaway LK. Changes in resting and walking energy expenditure and walking speed during pregnancy in obese women. Am J Clin Nutr. 2011;94(6):819–30.
Melzer K, Schutz Y, Boulvain M, Kayser B. Pregnancy-related changes in activity energy expenditure and resting metabolic rate in Switzerland. Eur J Clin Nutr. 2009;63(10):1185–91.
Van Raaij JM, Schonk C, Vermaat-Miedema SH, Peek ME, Hautvast JG. Energy before, cost of walking at a fixed pace during, and after pregnancy. Am J Clin Nutr. 1990;51:158–61.
Wu WH, Meijer OG, Jutte CP, Uegaki K, Lamoth CJC, de Wolf GS, et al. Gait coordination in pregnancy: transverse pelvic and thoracic rotations and their relative phase. Clin Biomech. 2002;19:480–8.
Butte NF, Wong WW, Treuth MS, Ellis KJ, Smith EOB. Energy requirements during pregnancy based on total energy expenditure and energy deposition. Am J Clin Nutr. 2004;79(1):1078–87.
Melzer K, Schutz Y, Kayser B. Normalization of basal metabolic rate for differences in body weight in pregnant women. Eur J Obst Gynecol Reprod Biol. 2011;159(2):480–1.
Löf M. Physical activity pattern and activity energy expenditure in healthy pregnant and non-pregnant Swedish women. Eur J Clin Nutr. 2011;65(12):1295–301.
Gordon KE, Ferris DP, Kuo AD. Metabolic and mechanical energy costs of reducing vertical center of mass movement during gait. Arch Phys Med Rehabil. 2009;90(1):136–44.
Ortega JD, Farley CT. Minimizing center of mass vertical movement increases metabolic cost in walking. J Appl Physiol. 2005;99(6):2099–107.
Waters RL, Mulroy S. The energy expenditure of normal and pathologic gait. Gait Posture. 1999;9:207–31.
Baker R, Hausch A, Mcdowell B. Reducing the variability of oxygen consumption measurements. Gait Posture. 2001;13:202–9.
Dumas GA, Reid JG, Wolfe LA, Griffin MP. Exercise, posture, and back pain during pregnancy. Part 2. Exercise and back pain. Clin Biomech. 1995;10(2):104–9.
Wu G, Siegler S, Allard P, Kirtley C, Leardini A, Rosenbaum D, et al. ISB recommendation on definitions of joint coordinate system of various joints for the reporting of human joiont motion - part I: ankle, hip, and spine. J Biomech. 2002;35:543–8.
Whittlesey SN, van Emmerik RE, Hamill J. The swing phase of human walking is not a passive movement. Mot Control. 2000;4(3):273–92.
Foti T, Davids JR, Bagley A. A biomechanical analysis of gait during pregnancy a biomechanical analysis of gait during pregnancy. J Bone Jt Surg. 2000;82-A(5):625–32.
Bennett BC, Abel MF, Wolovick A, Franklin T, Allaire PE, Kerrigan DC. Center of mass movement and energy transfer during walking in children with cerebral palsy. Arch Phys Med Rehabil. 2005;86(11):2189–94.
Kerrigan DC, Della CU, Marciello M, Riley PO. A refined view of the determinants of gait: significance of heel rise. Arch Phys Med Rehabil. 2000;81(8):1077–80.
Poppitt SD, Prentice AM, Jequier E, Schutz Y, Whitehead RG. Evidence of energy sparing in gambian women during pregnancy: a longitudinal study using whole-body calorimetry. Am J Clin Nutr. 1993;57:353–64.
Prentice AM, Goldberg GR, Davies HL, Murgatroyd PR, Scott W. Energy-sparing adaptations in human pregnancy assessed by whole-body calorimetry. Br J Nutr. 1989;62:5–22.
Unnithan VB, Dowling J, Frost G, Bar-or O. Role of mechanical power estimates in the O2 cost of walking in children with cerebral palsy. Med Sci Sports Exerc. 1999;31(12):1703–8.
ACSM (American College of Sports Medicine). ACSM’s guidelines for exercise testing and prescription. 9th ed. Philadelphia: Lippincott, Williams and Wilkins; 2013.
Nieman DC, Austin MD, Benezra L, Pearce S, McInnis T, Unick J, et al. Validation of Cosmed’s FitMate in measuring oxygen consumption and estimating resting metabolic rate. Res Sports Med. 2006;14(2):89–96.
Thomas SS, Buckon CE, Schwartz MH, Sussman MD, Aiona MD. Walking energy expenditure in able-bodied individuals: a comparison of common measures of energy efficiency. Gait Posture. 2009;29(4):592–6.
Schutz Y. Dietary fat, lipogenesis and energy balance. Physiol Behav. 2004;83(4):557–64.
Olney SJ, Macphail HEA, Hedden DM, Boyce WF. Work and power in hemiplegic cerebral palsy gait. J Phys Ther. 1990;70(7):431–8.
Schwartz MH, Koop SE, Bourke JL, Baker R. A nondimensional normalization scheme for oxygen utilization data. Gait Posture. 2006;24(1):14–22.
Willems PA, Cavagna GA, Heglund NC. External, internal and total work in human locomotion. J Experiemental Biol. 1995;198:379–93.
Burdett RG, Skrinar GS, Simon SR. Comparison of mechanical work and metabolic energy consumption during normal gait. J Orthop Res. 1983;1(1):63–72.
Winter DA. Human balance and posture standing and walking control during. Gait Posture. 1995;3:193. 214.
Abe D, Muraki S, Yasukouchi A. Ergonomic effects of load carriage on the upper and lower back on metabolic energy cost of walking. Appl Ergon. 2008;39(3):392–8.