What are some physiological differences between men and women that might affect fatigue and recovery?

Women generally have a higher proportion of type 1 muscle fibers (less fatigable), different patterns of substrate utilization with lower reliance on anaerobic and glucose metabolism, and smaller muscles which may lead to more efficient oxygen delivery and waste clearance. Estrogen in women helps prevent muscle damage and aids satellite cell lifecycle for recovery, though testosterone in men does similar things.

Why is there a demand for more female-focused research in exercise science?

Historically, exercise science literature has predominantly studied men, leading to questions about whether findings generalize to women. There's a push for targeted research focusing on areas with strong physiological rationales for sex-specific differences, like fatigue and recovery, rather than simply replicating all previous studies.

What were the key findings of Greg Knuckles' study on fatigue and recovery?

Women completed significantly more repetitions during the fatigue protocol (almost twice as many) compared to men. However, both sexes recovered at similar rates when assessing predicted one-rep max and soreness, despite the women performing more total volume.

What are the practical takeaways for training men versus women based on Greg's study?

For upper body exercise, women may be able to handle more volume or, at minimum, men may need longer rest periods between sets. The study suggests women are generally a little less fatigable than men.

What advice does Greg offer to someone considering a master's degree in exercise science?

Greg advises against trying to run multiple businesses during grad school. He suggests that a master's is beneficial for careers requiring it (like collegiate strength coaching), helps in deeply understanding scientific processes, and encourages finding an advisor who supports applied research interests.

What is betaine, and when was it first researched for performance?

Betaine, or trimethylglycine, was first discovered in beets. Early performance research in the 1950s looked at polio patients, with more sports-specific studies emerging around 2008-2009, some showing contradictory results in power versus muscular endurance.

What were Dr. Jason Cholewa's findings about betaine in his dissertation?

Dr. Cholewa's dissertation found that betaine supplementation led to improvements in lean mass and reductions in fat mass, but no significant improvements in performance metrics like 1RM or vertical jump. It was also noted to increase lean cross-sectional area of the arm.

Is betaine commonly found in supplements, and is it acutely effective?

Betaine is often found in multi-ingredient pre-workout supplements, usually at under-dosed amounts. It is not acutely effective; it requires two to four weeks of consistent use to accumulate in tissues and exert its effects.

What issues were identified in statistical reporting in exercise science research?

Many studies incorrectly report statistics, often using standard error instead of standard deviation (underestimating variance), or failing to report effect sizes or even primary hypotheses. This was observed across both high-tier and entry-level journals.

What is the current state and future outlook for higher education, according to Dr. Cholewa?

Higher education costs have significantly increased due to amenities and administrative bloat, not faculty pay. There's a philosophical debate on whether college should focus on economic preparation or truth-seeking. The current 'consumer model' for students and brick-and-mortar structures may not be sustainable, potentially leading to more online education.

Are printed academic journals still relevant, or is publishing moving entirely online?

With everything now available online, printed academic journals are largely obsolete. The shift to online publishing eliminates printing costs and is part of a larger movement influenced by technology, challenging traditional academic models.

Do experts like Dr. Cholewa use non-evidence-based practices with clients?

Dr. Cholewa mentions using cryotherapy with a bikini competitor client before a show. While there's no direct evidence for its subjective lean-enhancing effect for physique, it was done outside the training phase where adaptations occur, making potential negative impacts less likely.

Key Moments

Sex Differences in Fatigue and Recovery, and Dr. Jason Cholewa (Podcast Episode 2)

Stronger By Science

Education5 min read122 min video

May 30, 2019|4,850 views|144|12

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Key Moments

TL;DR

Podcast discusses sex differences in fatigue/recovery, betaine, and issues in higher education/publishing.

Key Insights

Women may be less fatigable than men in upper body exercises due to physiological differences, but recover at similar rates.

Betaine supplementation may aid in fat mass reduction and potentially lean mass increase, but shows limited performance benefits in current human research.

There's a significant need for more standardized and transparent statistical reporting in exercise science research.

Higher education faces challenges with rising costs and a perceived lack of return on investment, necessitating potential shifts toward online models and re-evaluation of its core purpose.

Academic publishing needs reform, with a growing movement towards open access and a critical re-examination of publication volume versus quality.

The line between experienced practitioners and academic researchers is blurring, leading to more applicable and ecologically valid scientific studies.

INTRODUCTION AND FEATS OF STRENGTH

The episode opens with host Eric Trexler introducing Master Greg Nuckols, who has just successfully defended his master's thesis. After acknowledging some initial technical difficulties and a brief, humorous recap of previous episode's potential spoilers for 'Avengers: Endgame' and 'Game of Thrones,' the discussion segues into an exciting segment. The 'Feats of Strength' section highlights incredible recent achievements in powerlifting, specifically John Haack's near-record total at 181 lbs, noted for its impressiveness even if he were drug-tested, and Mariana Gasparyan's world-record squat at 123 lbs, exceeding the male record by a significant margin. These feats underscore the remarkable strength demonstrated by athletes and spark conversations about the evolving standards in the sport.

SEX DIFFERENCES IN FATIGUE AND RECOVERY: NUCKOLS' STUDY

Greg Nuckols presents his master's thesis research investigating differences in fatigue and recovery rates between men and women. He outlines potential physiological reasons for these differences, including women's higher proportion of Type I muscle fibers, different substrate utilization impacting glycogen and lactate accumulation, and potentially smaller muscle size affecting blood flow. For recovery, estrogen's role in stabilizing muscle fibers and satellite cell function is discussed, though testosterone's similar effects in men complicate direct sex-based advantages. The importance of sex-specific research in exercise science, which has historically been male-dominated, is emphasized, highlighting the need for studies that generalize findings responsibly.

METHODOLOGY AND KEY FINDINGS OF THE FATIGUE STUDY

Nuckols details the methodology of his study, which involved participants completing six sessions including baseline testing, one-rep max estimations using load-velocity profiling, and a fatigue protocol. The fatigue protocol consisted of repeated sets of five reps at 75% of estimated max with 90-second rests until failure. Recovery was assessed through predicted one-rep max and subjective soreness. Key findings revealed that women completed significantly more repetitions (nearly double) during the fatigue protocol than men. However, both sexes demonstrated similar rates of recovery in terms of predicted one-rep max and subjective soreness, suggesting women might be less fatigable but recover at comparable rates, especially in upper-body exercises.

APPLICABLE TAKEAWAYS AND BETTAINE SUPPLEMENTATION

The discussion transitions to the practical applications of Nuckols' research, suggesting that for upper-body training, women may tolerate more volume, or men might require longer rest periods. The conversation then shifts to Dr. Jason Cholewa, an associate professor at Coastal Carolina University, discussing betaine supplementation (trimethylglycine). Cholewa explains its prevalence in beets and other vegetables, noting early research in polio patients and animals. His dissertation focused on betaine's effects on sports supplementation, performance, and body composition, finding improvements in lean mass and reductions in fat mass in pigs, but limited performance benefits and mixed results in human studies, particularly regarding strength and vertical jump.

BETTAINE'S ROLE AND SUPPLEMENT INDUSTRY TRENDS

Dr. Cholewa elaborates on betaine's potential mechanisms, suggesting it might draw water into muscles, similar to creatine, potentially aiding strength endurance or protein synthesis, though this is not yet conclusively proven in humans. He notes betaine's presence in many multi-ingredient pre-workout supplements, often at lower doses than used in research, and highlights that its effects may require consistent, long-term intake rather than acute use. The conversation touches on the common issue of underdosed ingredients in pre-workouts and the difficulty in isolating the effects of specific compounds when multiple ingredients like caffeine are present, which can offer ergogenic benefits.

CRITIQUES OF EXERCISE SCIENCE PUBLISHING AND HIGHER EDUCATION

The podcast delves into methodological and statistical reporting issues within exercise science. A study by Conrad Earnest and colleagues highlighted widespread problems, including incorrect reporting of statistics (e.g., standard error instead of standard deviation), lack of effect sizes, and absence of clear hypotheses. This lack of standardization and varying journal guidelines create challenges. The discussion broadens to higher education, questioning its return on investment and the perception of college as a '13th grade.' Authors express concern that rising costs are driven by amenities rather than academic quality, and that many students pursue degrees without genuine passion or even exercise habits, suggesting a need for reform in educational models and a philosophical re-evaluation of higher education's purpose.

THE FUTURE OF ACADEMIA AND PUBLISHING

The conversation explores potential future directions for academia and scientific publishing. The increasing shift towards online education and open-access publishing is noted as a response to evolving technology and cost pressures, challenging traditional models. The pressure to publish frequently is questioned, with a proposal for imposing publication limits to prioritize quality over quantity. The role of academic advisors in guiding students and the variability among master's programs are discussed, emphasizing the importance of finding a good fit for both students and advisors. The segment concludes by acknowledging that while the current systems have flaws, proactive efforts towards standardization and transparency are positive signs of growth and maturation in the field.

Mentioned in This Episode

●Supplements

●Products

●Software & Apps

●Companies

●Organizations

●Books

●Studies Cited

●Concepts

●People Referenced

Common Questions

Greg Knuckles' thesis investigates the differences in fatigue and recovery rates between males and females, specifically in the context of strength training.

Topics

Exercise Physiology Strength Training Neuroscience & the Brain Human Performance Learning & Education Science & Mathematics Academic Publishing Research Methodology Sports Nutrition Fatigue And Recovery Sex Differences In Strength Betaine Supplementation Higher Education Challenges

Mentioned in this video

Organizations

Springfield College

The institution where Dr. Jason Cholewa earned his PhD in Applied Exercise Physiology.

Coastal Carolina University

The institution where Dr. Jason Cholewa is an associate professor.

PubMed

A database of biomedical literature, mentioned as a source for research abstracts that some people might misinterpret without proper graduate training.

Stronger by Science

The name of the podcast and online coaching program that recently revamped its services and is offering a one-week sale.

IPF

A powerlifting federation whose scoring system (IPF points) was used by Greg to assess the relative competitiveness of male and female participants in his study.

peerJ

An open-access academic journal that Greg hopes to publish his master's thesis in because of its support for open science and lower publication costs.

University of North Carolina

The institution where Eric and Greg pursued their MA degrees in Exercise Physiology, which is an 'Arts' degree due to its emphasis on lab work over extensive coursework.

LSU

An example of a university that invested heavily in luxurious amenities (a lazy river) to attract students, contributing to rising education costs.

University of California System

A university system that failed to renew its journal subscription to Elsevier, symbolizing larger changes in academic publishing.

Media

Avengers: Endgame

A movie mentioned as having spoilers in the initial minutes of the podcast episode.

Game of Thrones

The final season of the TV series is mentioned as having spoilers in the initial minutes of the podcast episode, and is later compared to Avengers: Endgame.

Jaws 2

A movie mentioned by Eric to illustrate the confusion of watching a sequel without seeing the original, comparing it to his experience with the Marvel Cinematic Universe.

Infinity War

An Avengers movie that Greg preferred over Endgame.

People

Jesse Norris

A powerlifter whose previous raw total of 2033 lbs at 198 lbs body weight was mentioned as a benchmark for comparison with Jon Hack's total.

Shakira Ingram

Previously Shakira Holcomb, an impressive untested woman powerlifter in the 181 lbs class (1600 lbs total), though less than Jon Hack.

Conrad Earnest

The person behind the idea for the project on statistical reporting and exercise science, noting issues in peer-reviewed publications.

Andrew Vygotsky

A researcher mentioned for pushing transparency in methodology in sports science.

Albert Einstein

A physicist mentioned as an example of seminal scientists who achieved great impact with relatively few publications, contrasting with the modern pressure to publish frequently.

Brienne of Tarth

A character from Game of Thrones mentioned by Greg in a joking comparison about knighting others.

Steffi Cohen

A powerlifter who, along with Mariana Gasparin, broke both men's and women's world records for total in her weight class.

Eric Trexler

Host of the Stronger By Science podcast and Director of Education, who introduces Greg Knuckles and Dr. Jason Cholewa.

Mariana Gasparin

A powerlifter who squatted 573 lbs (260 kg) at 123 lbs body weight, setting a new record even surpassing the male world record in that weight class.

Jason Cholewa

Associate Professor at Coastal Carolina University and guest for the second segment, discussing betaine supplementation, research in exercise science, and higher education.

Jon Hack

A powerlifter celebrated for his impressive raw total of 1962 lbs at 181 lbs body weight, considered one of the most impressive raw totals of all time.

Peter Karpovich

A figure in exercise science mentioned as an example of seminal scientists from the field's past.

Companies

DuPont Nutrition

The company that produces BetaPower, a betaine product.

Now Foods

A company that sells trimethylglycine (betaine) as a supplement.

Elsevier

A major academic publisher that is criticized for its restrictive policies on sharing research, specifically for potentially suing authors who write about their own work outside their journals.

Software & Apps

Perceived Stress Questionnaire

A validated questionnaire used in Greg's study to assess participants' stress levels.

Supplements

Beta-Alanine

A supplement often found in pre-workouts that causes paresthesia (tingling) and needs to be accumulated in tissues to exert its effect.

Betaine

Also known as trimethylglycine, this compound was the focus of Dr. Jason Cholewa's dissertation and is discussed for its potential effects on strength, body composition, and performance.

Creatine

A well-researched supplement known for volumizing muscles, drawing water into them, similar to a proposed mechanism for betaine.

Niacin

A supplement that can cause a 'flush' sensation, especially on an empty stomach.

Caffeine

A common ergogenic ingredient in pre-workouts, often present in high doses, and whose effects are often attributed to the entire pre-workout formula.

Studies & Research

Davies et al. study

A recent study mentioned by Greg whose findings on recovery rates for lower body exercise (squats) contrasted with his own upper body exercise findings.

Concepts

Pittsburgh Sleep Quality Index

A validated questionnaire used in Greg's study to assess sleep quantity and quality.

Cryotherapy

A recovery method involving extremely cold temperatures, used by a client of Dr. Cholewa's before a bikini competition to potentially reduce inflammation and enhance definition.

DEXA Scan

A body composition measurement technique used in Greg's master's study to assess participants' arm lean mass.

Bulgarian Method

A high-frequency, high-intensity training protocol mentioned jokingly by Greg to explain why he didn't want his recovery assessments to induce additional fatigue.

Polio

Polio patients were the subject of one of the earliest studies on betaine supplementation in the 1950s, showing improvements in performance metrics.

AMPK mRNA expression

Betaine is suggested to increase AMPK mRNA expression in animals, which could suppress lipogenesis and help with fat loss.

Marvel Cinematic Universe

The franchise that includes Avengers movies, which Eric had not seen before watching Avengers: Endgame.

CrossFit

Jason Cholewa plans to study betaine supplementation in CrossFit athletes to see its effect on strength endurance and body composition.

Products

BetaPower

A betaine product from DuPont Nutrition, potentially available for wholesale rather than retail.

Books

The Undoing Project

A book mentioned by Jason Cholewa about psychologists in the 1970s and their theories, relating to the challenges of statistical understanding in various fields.

CONSORT paper

A guideline paper providing recommendations for how to report statistical findings in research, which many journals in exercise science have not yet adopted.

Legislation & Policy

Creative Commons BY 4.0 license

A public domain license that allows results to be shared freely with attribution, which peerJ supports.