Director, Physical Activity Centre of Excellence (PACE)
Director, McMaster Centre for Nutrition, Exercise, and Health Research
The maintenance of a metabolically active skeletal muscle mass is to a great extent underappreciated, particularly where optimal health is concerned. Skeletal muscle, besides its obvious role in locomotion, is a highly important thermogenic (i.e., energy consuming) tissue and the prime determinant of our basal metabolic rate, which for most of us is the largest single contributor to daily energy expenditure. Hence, declines in skeletal muscle mass can lead to increases in body fat mass. Because of its oxidative capacity (i.e., mitochondrial content) skeletal muscle is also a large site of fat oxidation, potentially playing a role in maintaining lipoprotein (cholesterol) and triglyceride homeostasis. Skeletal muscle is also, mostly by virtue of its mass, the primary site of blood glucose disposal; hence, maintaining skeletal muscle mass would also play a role in reducing risk for development of type II diabetes. Finally, the decline in maximal aerobic capacity with age, and with other muscular wasting conditions, including weight loss, has also been found to be due, to a large degree, to a decline in skeletal muscle mass and skeletal muscle quality. My research program has at its centre the following research question, what factors serve to maintain, increase, or decrease skeletal muscle mass? In addition, my research does not only address the absolute mass of skeletal muscle, but also its quality as assessed by the quantity of force it can generate, but also by the metabolic activity of various enzymes and energy consuming pathways.
We use a human model of resistance or aerobic exercise, immobilization, or aging to study the processes that govern: muscle accretion, in the case of resistance exercise; atrophy, in the case of immobilization; and sarcopenia, in the case of aging. In addition, my research group has studied the interaction of feeding different protein composition and varied meal timing on the processes regulating hypertrophy and disuse atrophy. We employ stable isotope tracers of amino acids to metabolically trace the fate of ingested proteins. Muscle biopsies provide us with mechanistic information regarding processes that regulate protein accretion and degradation. We use Western blotting, RT-PCR, histological, and immunohistochemical methods to examine these mechanisms. I am also very interested in conditions in which muscle wasting occurs, particularly in the elderly.
Published review articles in 2015 (all trainees underlined)
- R.W. Morton, C. McGlory, and S.M. Phillips. Nutritional interventions to augment resistance training-induced skeletal muscle hypertrophy. Front. Physiol. 6:245, 2015.
- C. McGlory, A.J. Hector, and S.M. Phillips. The influence of mechanical loading on skeletal muscle protein turnover. Cell. Mol. Exerc. Physiol. 4(1): e8, 2015.
- S.M. Phillips. Nutritional Supplements in Support of Resistance Exercise to Counter Age-Related Sarcopenia. Adv. Nutr. 6(4):452-460, 2015.
- S.M. Phillips, V. Fulgoni, R.P. Heaney, T.A. Nicklas, J.L. Slavin, and C.M. Weaver. Commonly consumed protein foods contribute to nutrient intake, diet quality, and nutrient adequacy. Am. J. Clin. Nutr. 101(Suppl). 1346S-1352S, 2015.
- M.C. Devries and S.M. Phillips. Supplemental protein in support of muscle mass and health: advantage whey. J. Food Sci. 80(Suppl 1): A8-A15, 2015.
- C.J. Mitchell, T.A. Churchward-Venne, D. Cameron-Smith, S.M. Phillips. What is the relationship between acute measures of muscle protein synthesis and changes in muscle mass? J. Appl. Physiol. 118(4):495-497, 2015.
- C.H. Murphy, A.J. Hector, and S.M. Phillips. Considerations for protein intake in managing weight loss in athletes. Eur. J. Sports Sci. 15(1): 21-28, 2015.
Published journal articles in 2015 (trainees underlined)
- J.P. Nederveen, S. Joanisse, C.M. Séguin, K. Bell, S.K. Baker, S.M. Phillips, and G. Parise. The effect of exercise mode on the acute response of satellite cells in old men. Acta Physiol. (Oxf). 215(4): 177-190, 2015.
- M. Mônico-Neto, H.K.M. Antunes, K.S. Lee, S.M. Phillips, S.Q.C. Giampá, H. Souza, M. Dáttilo, A. Medeiros, W.M. Moraes, S. Tufik, M.T. de Mello. Resistance training minimizes catabolic effect induced by sleep deprivation in rats. Appl. Physiol. Nutr. Metab. 40(11): 1143-1150, 2015.
- K.E. Bell, C. Séguin, G. Parise, S.K. Baker, and S.M. Phillips. Day-to-day changes in muscle protein synthesis in recovery from resistance, aerobic, and high-intensity interval exercise in older men. J. Gerontol. A Biol. Sci. Med. Sci. 70(8): 1024-1029, 2015.
- A. Philp, S. Schenk, J. Perez-Schindler, D.L.Hamilton, L. Breen, E. Laverone, S. Jeromson, S.M. Phillips, and K. Baar. Rapamycin does not prevent increases in myofibrillar or mitochondrial protein synthesis following endurance exercise. J.Physiol. 593(18): 4275-4284, 2015.
- W.J. Smiles, J.L. Areta, V.G. Coffey, S.M. Phillips, D.R. Moore, T. Stellingwerff, L.M. Burke, J.A. Hawley, D.M. Camera. Modulation of Autophagy Signaling with Resistance Exercise and Protein Ingestion Following Short-Term Energy Deficit. Am. J. Physiol. Regul. Intergr. Comp. Physiol. 309(5): R603-R612, 2015.
- M.C. Devries, L.Breen, M. Allmen, M.J. MacDonald, D.R. Moore, E.A. Offord, M-N. Horcajada, D. Breuille, and S.M. Phillips. Low load resistance training during step-reduction attenuates declines in muscle and strength and enhances anabolic sensitivity in older men. Phys.Rep. 3(8): e12493, 2015.
- C.H. Murphy, T.A. Churchward-Venne, C.J. Mitchell, N.M. Kolar, A. Kassis, L.G. Karagounis, L.M. Burke, J.A. Hawley and S.M. Phillips. Hypoenergetic diet-induced reductions in myofibrillar protein synthesis are restored with resistance training and balanced daily protein ingestion in older men. Am. J. Physiol. Endo. Metab. 308(9): E734-743, 2015.
- C.J. Mitchell, S.Y. Oikawa, D.L. Ogborn, L.G.MacNeil, M.A. Tarnopolsky, S.M. Phillips. Daily chocolate milk consumption does not enhance the effect of resistance training. 40(2): 199-202, 2015.
- A.J. Hector, G.R. Marcotte, T.A. Churchward-Venne, C.H. Murphy, L. Breen, M. von Allmen, S.K. Baker, and S.M. Phillips. Whey protein supplementation preserves postprandial myofibrillar protein synthesis during short term energy restriction in overweight and obese adults. J. Nutr. 145(2): 246-252, 2015.
- D.S. Rowlands, A.R. Nelson, S.M. Phillips, J.A. Faulkner, J. Clarke, N.A. Burd, D.R. Moore, and T. Stellingwerff. Protein-Leucine fed dose effects on muscle protein synthesis after endurance exercise. Med. Sci. Sports Exerc. 47(3): 547-555, 2015.
- D.M. Camera, D.W. West, S.M. Phillips, T. Rerecich, T. Stellingwerff, J.A. Hawley, V.G. Coffey. Protein Ingestion Increases Myofibrillar protein synthesis after concurrent exercise. Med. Sci. Sports Exerc. 47(1): 82-91, 2015.
- D.R. Moore, T.A. Churchward-Venne, O. Witard, L. Breen, N.A. Burd, K.D. Tipton, and S.M. Phillips. Protein ingestion to stimulate myofibrillar protein synthesis requires greater relative protein intakes in healthy older versus younger men. J. Gerontol. A Biol. Sci. Med. Sci. 70(1): 57-62, 2015.
|PhD||University of Waterloo||1995|
|Amy Hector (Medical Sciences)|
|Post Doc||Michaela De Vries|