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Darryn  Willoughby, Ph.D. - Baylor University . Baylor, TX, US

Darryn Willoughby, Ph.D. Darryn  Willoughby, Ph.D.

Professor of Health, Human Performance and Recreation | Baylor University


Dr. Willoughby is an associate professor of health, human performance and recreation at Baylor University.



Darryn  Willoughby, Ph.D. Publication



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THE SCIENCE OF MUSCLE GROWTH with Dr Darryn Willoughby & Phil Graham Prof. Darryn Willoughby: Creatine How To Maximize Protein Synthesis To Improve Muscle Growth | Olympia Fitness Weekend



Dr. Darryn S. Willoughby is an associate professor of health, human performance and recreation and directs Baylor University's Exercise and Biochemical Nutrition Laboratory. He studies molecular physiology and biochemistry of exercise and nutrition, cellular and molecular physiology of muscle, exercises and sport nutrition, neuromuscular exercise physiology and strength training and sport conditioning.

Willoughby specifically researches the effects of training and nutritional intervention on the physiological, biochemical and molecular mechanisms regulating skeletal muscle strength, hypertrophy and atrophy in athletes. He has published articles on his findings in Journal of Nutrition and Metabolism, International Journal of Sport Nutrition and Exercise Metabolism and Journal of Medicinal Food.

Willoughby is a certified sport nutritionist, exercise physiologist, nutrition specialist and strength and conditioning specialist. He is a fellow of the International Society of Sports Nutrition, the American Society of Exercise Physiologists and the American College of Sports Medicine. He has been on the Baylor faculty since 2002.

After receiving his bachelor's degree in health and fitness from Tarleton State University in 1986, he earned his master of education degree there in 1989. He earned his doctoral degree in neuromuscular exercise physiology and biochemistry from Texas A&M University in 1993.

Industry Expertise (3)

Education/Learning Fitness Research

Areas of Expertise (9)

Effects of Training Molecular Physiology Biochemistry of Exercise Nutrition Cellular and Molecular Physiology of Muscle, Exercises and Sports Nutrition Neuromuscular Exercise Physiology Strength Training Sport Conditioning.

Education (3)

Texas A&M University: Ph.D., Neuromuscular exercise physiology and biochemistry 1993

Tarleton State University: M.Ed., Health and fitness 1989

Tarleton State University: B.S., Health and fitness 1986

Media Appearances (3)

Professor Holds and Calms Student's Baby Through Lecture After Sitter Called in Sick

ABC News  online


A Baylor University professor from Waco, Texas, is getting a lot of kudos on the Internet for stepping up after a student's babysitter fell through.

Katy Humphrey, 33, told ABC News today that her professor Darryn Willoughby held her 4-month-old daughter, Millie, through an hour-long lecture earlier this month after her babysitter called in sick.

"I showed up to class a couple minutes late and then, on top of that, Millie started to fidget and fuss in her carrier," the retired Marine said. "Dr. Willoughby saw me trying to soothe her, so he came by and picked her up for me."

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Baylor Ranks Among Most Productive Research Universities

Baylor Media Communications  online


Baylor University is among the most productive research universities in the nation, according to a new study released by Academic Analytics, a corporation based in Stony Brook, N.Y. that measures faculty scholarly productivity. Baylor also placed in the top 10 among large research universities in Texas, defined as institutions with 15 or more Ph.D. programs across multiple disciplines.

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Riding it out

The TCU Magazine  online

There is no sense sitting around waiting for a cure for paralysis, says kinesiology professor Darryn Willoughby. He's helping those with spinal cord injuries to possibly walk again -- and they get a workout in the process.

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Articles (5)

Intramuscular Anabolic Signaling and Endocrine Response Following Resistance Exercise: Implications for Muscle Hypertrophy Sports Medicine


Maintaining skeletal muscle mass and function is critical for disease prevention, mobility and quality of life, and whole-body metabolism. Resistance exercise is known to be a major regulator for promoting muscle protein synthesis and muscle mass accretion. Manipulation of exercise intensity, volume, and rest elicit specific muscular adaptations that can maximize the magnitude of muscle growth. The stimulus of muscle contraction that occurs during differing intensities of resistance exercise results in varying biochemical responses regulating the rate of protein synthesis, known as mechanotransduction. At the cellular level, skeletal muscle adaptation appears to be the result of the cumulative effects of transient changes in gene expression following acute bouts of exercise. Thus, maximizing the resistance exercise-induced anabolic response produces the greatest potential for hypertrophic adaptation with training. The mechanisms involved in converting mechanical signals into the molecular events that control muscle growth are not completely understood; however, skeletal muscle protein synthesis appears to be regulated by the multi-protein phosphorylation cascade, mTORC1 (mammalian/mechanistic target of rapamycin complex 1). The purpose of this review is to examine the physiological response to resistance exercise, with particular emphasis on the endocrine response and intramuscular anabolic signaling through mTORC1. It appears that resistance exercise protocols that maximize muscle fiber recruitment, time-under-tension, and metabolic stress will contribute to maximizing intramuscular anabolic signaling; however, the resistance exercise parameters for maximizing the anabolic response remain unclear.

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Effect of resistance exercise intensity on the expression of PGC-1α isoforms and the anabolic and catabolic signaling mediators, IGF-1 and myostatin, in human skeletal muscle Applied Physiology, Nutrition, and Metabolism


The purpose of this study was to investigate the acute messenger (mRNA) expression of the peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) isoforms, insulin-like growth factor-1Ea (IGF-1Ea), and myostatin in response to 2 resistance exercise intensities. In a uniform-balanced, crossover design, 10 participants performed 2 separate testing sessions involving a lower body resistance exercise component consisting of a lower intensity (50% of 1-repetition maximum; 1RM) protocol and a higher intensity (80% of 1RM) protocol of equal volumes. Muscle samples were obtained at before exercise, 45 min, 3 h, 24 h, and 48 h postexercise. Resistance exercise did not alter total PGC-1α mRNA expression; however, distinct responses of each PGC-1α isoform were observed. The response of each isoform was consistent between sessions, suggesting no effect of resistance exercise intensity on the complex transcriptional expression of the PGC-1α gene. IGF-1Ea mRNA expression significantly increased following the higher intensity session compared with pre-exercise and the lower intensity session. Myostatin mRNA expression was significantly reduced compared with pre-exercise values at all time points with no difference between exercise intensity. Further research is needed to determine the effects of the various isoforms of PGC-1α in human skeletal muscle on the translational level as well as their relation to the expression of IGF-1 and myostatin.

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The Effectiveness of Whole Body Cryotherapy Compared to Cold Water Immersion: Implications for Sport and Exercise Recovery International Journal of Kinesiology & Sports Science


Cryotherapy is the process of cooling the body, is typically used therapeutically, and is often used as a method of recovery relative to sport and exercise performance. The purpose of this review is to compare the current literature on WBC to that of CWI and determine whether WBC provides any additional enhancements for sport and exercise recovery. These include tissue temperature reduction, markers of muscle damage, markers of inflammation, and parasympathetic reactivation. Method: Common methods of cryotherapy include cold water immersion (CWI), ice packs, ice massages, and gel or cooling creams. CWI is the most common method among athletes; however, a new form of cryotherapy, known as whole-body cryotherapy (WBC), has recently emerged. Since its introduction, WBC has grown in popularity among practitioners and athletes. WBC involves short exposures (generally between 2-4 minutes) to very cold air (-100o C to -140o C) in a controlled room and setting. Furthermore, many of the studies on WBC were observational and did not contain a control group. Conclusion: Despite its growing popularity, the alleged benefits of WBC are largely based on anecdotal evidence as randomized, clinically-controlled studies regarding its efficacy are limited.

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Effect of Pre-Exercise Nutrition on Human Skeletal Muscle UCP3 Expression International Journal of Exercise Science


BACKGROUND: Increased UCP3 expression in skeletal muscle after exercise may be attributed to elevated free fatty acids (FFA) that are known to directly activate UCP3 expression. Pre-exercise glucose consumption has shown to blunt UCP3 expression in response to exercise. Since glucose ingestion before and during exercise is typically not a common practice, the goal of the present study was to assess the effect of a multi-macronutrient meal (drinkable shake) in the pre-exercise period towards human skeletal muscle UCP3 expression.

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Creatine supplementation post-exercise does not enhance training-induced adaptations in middle to older aged males European Journal of Applied Physiology


The present study evaluated the effects of creatine monohydrate (CrM) consumption post-exercise on body composition and muscle strength in middle to older males following a 12-week resistance training program.

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