HoldsUp

Chris McGlory

Queen's University

Chris McGlory is an assistant professor at Queen's University in Kingston, Ontario, Canada, specializing in muscle physiology and aging. His research investigates the molecular mechanisms governing muscle protein synthesis, proteostasis, and skeletal muscle adaptation to resistance exercise. Additionally, his published work examines the physiological effects of omega-3 fatty acid supplementation, muscle disuse, and sex-based differences in mitochondrial and exercise responses.

45 claims checked on air: 1 overstated 43 supported 1 unverified

What they said on air - citing their own research

7 citing their own research

0:21:10supportedmoderatetheir own paperChris McGlory, PhD, on the Anabolic Potential of Omega-3 Fat

In a 2017 study by Tanner Stokes and Chris McGlory in older pre-diabetic individuals, reducing daily steps below 1,000 for two weeks downregulated muscle protein synthesis and compromised insulin sensitivity, which failed to recover after two weeks of normal activity.

"I did a study as a postdoc with Tanner Stokes when we were in Stu Phillips's lab where we subjected older people to reduced daily step counts. I believe it was below a thousand steps per day, and that kind of mimicked what people would experience during, say, the pandemic when they were being quarantined for two weeks, or influenza, or the step count typically experienced in hospital. And what we found was that there was a downregulation of protein synthesis, and this was in older, pre-diabetic populations. And it wasn't fully recovered after two weeks of returning to activities." (said at 0:21:10)

A prospective clinical trial conducted in Stuart Phillips's laboratory by McGlory, Stokes, and colleagues investigated the effects of 14 days of step reduction (<1,000 steps/day) followed by 14 days of habitual activity recovery in 22 overweight, prediabetic older adults (mean age 69 years). The study confirmed that 2 weeks of acute physical inactivity significantly lowered integrated muscle protein synthesis rates and impaired glycemic control and insulin sensitivity (elevating HOMA-IR and glucose/insulin AUC, while lowering the Matsuda insulin sensitivity index). Crucially, neither muscle protein synthesis nor insulin sensitivity returned to baseline levels after 14 days of resuming normal activity.

0:27:39supportedmoderatetheir own paperChris McGlory, PhD, on the Anabolic Potential of Omega-3 Fat

Approximately four weeks of high-dose omega-3 supplementation is required to see a substantial increase in the omega-3 profile of human skeletal muscle.

"Using a protocol that we'd worked on in Scotland where we knew it took around four weeks of high-dose omega-3s to see a substantial increase in the omega-3 profile of the muscle" (said at 0:27:39)

High-dose omega-3 supplementation (e.g., 5 g/day of fish oil) progressively increases omega-3 polyunsaturated fatty acid (n-3 PUFA) incorporation into human skeletal muscle lipid and phospholipid pools over a 4-week period. In a time-course trial tracking muscle lipid changes at 1, 2, and 4 weeks of high-dose fish oil supplementation, skeletal muscle n-3 PUFA content increased significantly by week 2 and continued to rise through week 4, establishing a 4-week loading period as standard protocol in subsequent human immobilization and muscle physiology trials.

0:28:40supportedmoderatetheir own paperChris McGlory, PhD, on the Anabolic Potential of Omega-3 Fat

In Dr. McGlory's study on young women, four weeks of high-dose omega-3 supplementation mitigated the decline in muscle size during two weeks of single-leg immobilization and accelerated muscle mass recovery afterwards.

"And what we really found was very surprising to us. It seemed like the omega-3s were completely protective, at least from a mass point of view, and they took the edge off the decline in muscle size as measured by MRI... And, you know, there was that protection, and then the important thing I think when we look at it is that actually it helped the people in the omega-3 group recover their muscle earlier than the people in the control group." (said at 0:28:40)

A randomized controlled trial led by Dr. Chris McGlory (PMID: 30629458) evaluated 20 healthy young women who consumed either 5 g/day of omega-3 fatty acids or a control oil starting 4 weeks before 2 weeks of unilateral leg immobilization, followed by 2 weeks of recovery. The decline in muscle volume following immobilization was significantly attenuated in the omega-3 group compared to the control group (8% vs. 14%), and muscle volume returned to pre-immobilization baseline levels during recovery in the omega-3 group but remained significantly reduced in controls.

0:29:35supportedmoderatetheir own paperChris McGlory, PhD, on the Anabolic Potential of Omega-3 Fat

Dr. McGlory's immobilization study measured muscle protein synthesis rates using deuterium and found higher rates of protein synthesis in the omega-3 group compared to control.

"And from a mechanistic point of view, we used deuterium to assess rates of muscle protein synthesis, and consistent with the previous work by Bettina Mittendorfer's group and Gordon Smith, we found that in the omega-3 group, there was higher rates of protein synthesis, which would kind of again corroborate the mechanisms of action of omega-3s, which is to enhance the protein synthetic response to daily protein feeding." (said at 0:29:35)

In a randomized trial by McGlory et al. (2019), 20 healthy young women underwent 2 weeks of unilateral leg immobilization preceded by 4 weeks of supplementation with either 5 g/day of omega-3 fatty acids or a sunflower oil control. Using deuterium oxide tracer methodology to evaluate integrated daily rates of myofibrillar protein synthesis (MyoPS), researchers found that MyoPS was significantly higher in the omega-3 supplementation group compared to the control group at all measured timepoints, which coincided with attenuated muscle atrophy.

0:43:15supportedmoderatetheir own paperChris McGlory, PhD, on the Anabolic Potential of Omega-3 Fat

Supplementation with approximately 5 grams of omega-3s takes about 4 weeks to induce a significant change in skeletal muscle phospholipid profile, plateauing between 6 and 8 weeks.

"And in skeletal muscle, we know if you take around 5 grams of omega-3s—3 grams of EPA, 2 grams of DHA, say, as a combination—you'll probably see a small change after about two weeks in the muscle. You see a rapid change in the blood, but it takes around four weeks before you start to see the kind of big difference. And with that dose, it typically will level off. We've seen this in the FASEB paper we did with disuse atrophy—it wasn't the primary aim of the paper, but between six and eight weeks, it seemed to level off. And this is in the muscle phospholipid profile." (said at 0:43:15)

Human clinical trials evaluating high-dose omega-3 polyunsaturated fatty acid supplementation (~5 g/day of EPA and DHA) demonstrate that EPA and DHA are incorporated into human skeletal muscle phospholipid membranes over several weeks. A clinical study examining the kinetics and sex differences of 5 g/day EPA+DHA supplementation across 8 weeks (with muscle sampling at baseline, week 6, and week 8) confirmed significant muscle phospholipid enrichment that peaks or levels off between weeks 6 and 8. Previous clinical trials by McGlory and colleagues using 5 g/day of omega-3 fatty acids in human disuse atrophy protocols similarly demonstrated time-dependent muscle phospholipid incorporation leading to clinical attenuation of disuse atrophy.

1:09:55supportedmoderatetheir own paperChris McGlory, PhD, on the Anabolic Potential of Omega-3 Fat

Graham Holloway showed that feeding omega-3s to younger people alters ADP sensitivity and ADP-stimulated respiration in human skeletal muscle mitochondria.

"For example, Graham has shown a number of years ago that feeding omega-3s in younger people can affect ADP sensitivity, or ADP-stimulated respiration, in the mitochondria in human skeletal muscle." (said at 1:09:55)

Studies led or co-authored by Dr. Graham Holloway demonstrated that dietary omega-3 fatty acid supplementation in young healthy humans alters mitochondrial function in skeletal muscle. Specifically, a 2014 clinical study in young healthy men showed that 12 weeks of omega-3 fish oil supplementation significantly increased mitochondrial membrane EPA and DHA content and enhanced mitochondrial ADP sensitivity (reduced apparent Km) in permeabilized skeletal muscle fibers. In addition, a 2019 trial in young healthy women demonstrated that omega-3 supplementation mitigated disuse-induced decreases in ADP-stimulated skeletal muscle mitochondrial respiration.

1:29:14supportedmoderatetheir own paperChris McGlory, PhD, on the Anabolic Potential of Omega-3 Fat

Endurance exercise promotes capillarization in skeletal muscle, enhancing blood flow and nutrient delivery, and activates satellite cells to donate nuclei that support hypertrophy from resistance exercise.

"you precondition or you perform aerobic exercise and that may enhance capillarization, so, you know, facilitating blood delivery to the to the muscle cell. And then when you perform resistance exercise, the muscle is is primed to receive more nutritional, you know, insulin and and amino acids to enhance the response, the protein synthetic response, to the to resistance exercise. ... And endurance exercise may not only enhance nutrient delivery, but also activate satellite cells where they can donate their nuclear material to and to support the growth response to resistance training." (said at 1:29:14)

The claim is supported by clinical trials investigating aerobic preconditioning and capillarization in muscle hypertrophy. Research demonstrates that performing aerobic/endurance conditioning prior to resistance training increases capillary density and satellite cell content in skeletal muscle, which enhances muscle fiber cross-sectional area and myonuclear responses during subsequent resistance training (PMID: 35971745, PMID: 27897408).

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