In this investigative “Wellness Girl chat,” Dr. Kelsy Vick breaks down how fitness trackers estimate caloric expenditure—and why those numbers can be misleading for assessing workout effort, effectiveness, or weight loss. She defines calories (including the difference between food-label “calories” and kilocalories), explains total daily energy expenditure, and outlines what wearables typically model: basal metabolic rate (BMR) plus active energy expenditure, while often failing to capture thermic effect of food and non-exercise activity thermogenesis (NEAT). She reviews how BMR is estimated from static equations using age, sex, height, and weight (with limitations and common error ranges), then explains how active calories rely on proprietary algorithms driven largely by heart rate, supported by sensors like accelerometers, gyroscopes, barometers, GPS, and (for Oura) skin temperature—often switching sensor priorities based on the selected activity.

The episode also connects heart rate to oxygen consumption and energy expenditure, explains VO2 and the lab-based VO2 max testing process, and shows how wearables use heart-rate-based VO2 relationships to estimate calories. Dr. Vic compares common devices: Apple Watch (Move vs Total Calories, activity classification, VO2 feature accuracy cited within 4% when using VO2 integration), Whoop (step-free strain model, continuous heart rate monitoring, algorithm shifts based on heart rate reserve), Oura Ring (finger-based sensing, emphasis on resting metrics, temperature and sleep inputs for BMR, MET-based intensity categories with user-reported effort), Garmin (GPS- and pace-informed VO2 estimates, cycling power-based calculations, with studies showing wide accuracy ranges and underestimation at low and very high intensities due to heart-rate lag and anaerobic work), and Fitbit (older models leaning more on accelerometer data, newer models incorporating heart rate).

Dr. Vick summarizes research findings showing large real-world error in wearable calorie estimates, including a Stanford Benchmark study (most accurate device averaging 27% off; least accurate 93% off, with factors like skin color and BMI affecting results), a 2025 head-to-head comparison reporting varying under- and over-estimation across devices, and a systematic review where no brand consistently met acceptable accuracy limits. She notes that resting heart rate and step count are generally more accurate than calorie burn estimates, while sleep duration is moderately accurate and sleep staging is weak. The takeaway: calorie metrics may be useful for broad trends, but shouldn’t drive dietary or training decisions; she recommends emphasizing other wearable metrics such as heart rate, VO2/VO2 max, heart rate variability, and recovery instead.

Resources:

https://www.empirical.health/blog/apple-watch-calories-accuracy/

https://www.apple.com/health/pdf/Heart_Rate_Calorimetry_Activity_on_Apple_Watch_November_2024.pdf

https://pmc.ncbi.nlm.nih.gov/articles/PMC5738849/

https://pmc.ncbi.nlm.nih.gov/articles/PMC9950693/

https://blogs.sas.com/content/efs/2025/06/25/can-you-trust-your-smartwatch-a-deep-dive-into-calorie-burn-estimates/

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00:00 Calories Culture Backstory

02:49 What Trackers Claim

04:05 What Is A Calorie

04:51 TDEE Basics BMR Active

06:41 BMR Formula Limits

08:28 Sensors And Algorithms

11:55 Heart Rate And VO2

12:55 VO2 Lab Gold Standard

15:35 Apple Watch Breakdown

17:14 Whoop Strain Model

18:57 Oura Ring And METs

22:14 Garmin VO2 And GPS

26:03 Fitbit And Accuracy Studies

29:01 How To Use Calories

31:08 Wrap Up And Takeaways

With the Lunar New Year, Olympics, and Traditional Chinese Medicine practices on social media right now, Dr. Kelsy Vick revisits her June convo with TCM practitioner Dr. Felice Chan and pulls out the most practical takeaways. We cover core TCM ideas (qi, blood, jing), how imbalance can show up like missed periods in hard-training athletes, and easy ways to apply TCM day-to-day: more warmth for digestion, gentler movement for stress and cortisol balance, and blood-building foods during your period. Kelsy also shares Dr. Felice's travel digestion tips (breathwork, hydration/electrolytes, ginger tea) and what TCM might look like in elite training—think acupuncture, cupping, massage techniques, and carefully dosed herbs.

Episode with Dr. Felice Chan:

https://wellness-big-sis-the-pod.captivate.fm/episode/dr-felice-chan/

Research articles:

https://pmc.ncbi.nlm.nih.gov/articles/PMC9219272/

https://pmc.ncbi.nlm.nih.gov/articles/PMC9331350/

https://pubmed.ncbi.nlm.nih.gov/40251536/

Eileen Gu article:

https://en.people.cn/n3/2022/0209/c90000-9955574.html

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Dr. Kelsy Vick closes out the Goalchella Podcast Festival with self-selected highlights from expert interviews recorded from November through early February, created around common New Year’s goals for women. She revisits key moments from: Dr. Sam Moore on female physiology, menstrual-cycle awareness, resilience in training, energy availability, and the importance of carbohydrates and progressive strength training; Dr. Emily Hilz on the dopamine reward system, estrogen sensitivity across the menstrual cycle, and how hormonal states can influence reward seeking and motivation, plus an overview of endocrine disrupting chemicals (including bisphenols, phthalates, PFAAS, parabens, and flame retardants), where they’re found, and why “safe” levels are complicated by sensitive developmental windows and mixture effects; Dr. Lisa Neff on how relationship quality impacts mental and physical health, including research linking social relationship quality to mortality risk and evidence that hostile couple communication slows wound healing, and how everyday stressors spill over into relationships by reducing connection, increasing negativity and blame, worsening conflict communication, and undermining support; Katie (a certified credit counselor and Bankrate writer) on women-centered approaches to money, breaking habits like impulse shopping and carrying credit card balances, separating emotions from money, and using travel credit cards and welcome bonuses responsibly to reduce travel costs; and Aaron (a certified habit coach) on outcome vs process vs identity goals, the behavior science of cues, ability/self-efficacy, and reward, and designing environments to support habit formation. She thanks listeners for supporting the series, invites topic and guest requests, and transitions back to regular episodes of Wellness Fix the Pod.

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Why do New Year goals fail — even when motivation is high? In this Goalchella finale, we dive into the neuroscience of habit formation with expert Erin to unpack what actually happens in the brain when we try to build new habits or break old ones.

We explore why motivation fades, how discipline is built, and whether forming a new habit is harder than breaking an existing one. This episode breaks down intrinsic vs. extrinsic motivation, the role of rewards, and how your environment — including social settings like alcohol-centered events — can either support or sabotage your goals.

If you’ve ever set vague goals like “be less stressed” or “be more mindful” and felt stuck, we explain why unclear goals are harder for the brain to execute — and how to make habits more achievable, sustainable, and measurable in 2026.

We also talk about Erin’s upcoming book, how she used the science of habit formation to support her own discipline during the writing process, and her certification for professionals who want to create meaningful behavior change.

This episode perfectly wraps up the Goalchella podcast festival and gives you the tools to turn inspiration into lasting change — whether you’re working on your own habits or helping others do the same.

Links/Research Articles:

​​https://www.erinlaverone.com/

https://www.habitcoachpro.com/

Book: Do The Thing: A Science Backed Process To Help You Take Action Even When Motivation Fails and Life Gets Messy (Coming so soon!!!!)

Book Launch Ambassador: (I signed up for Tier 1!) https://docs.google.com/forms/d/e/1FAIpQLSfqtzVsstm6l6BKUOpvGrBDtlAVFuIbBFlqHHETR5FzOj7L6A/viewform?pli=1

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​​Travel can be one of the most empowering ways to invest in yourself — but it requires intentional planning, smart saving, and creative strategies. In this Goalchella episode, we explore how women can prioritize travel in 2026 while strengthening their financial wellness.

We discuss actionable steps to turn travel dreams into reality, from setting up dedicated travel savings accounts and budgeting for your trips, to visualizing your ideal experiences and bringing them to life through social media inspiration. Our guest shares insider tips on making travel more budget-friendly, including using credit card points, off-season travel, flight trackers, and local strategies to stretch your dollar.

We also cover favorite credit cards for women looking to maximize rewards, and the importance of understanding your finances as a tool for freedom, not stress. Whether you’re saving for a honeymoon, a backpacking adventure, or exploring new cities, this episode equips you to travel more, spend smarter, and take control of your financial wellness — so your money supports the life and adventures you truly want.

Links/Research Articles:

https://www.bankrate.com/authors/katie-kelton/

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Endocrine-disrupting chemicals (EDCs) are all around us — in everyday products, food packaging, and even the environment — yet their effects on our hormonal systems and overall health are often overlooked. In this Goalchella episode, we sit down with Dr. Emily to explore what EDCs are, how they interfere with hormonal communication, and the systems in our bodies they impact — from the gonads and thyroid to bone, fat, and the brain.

Dr. Emily dives into her research on how early-life exposure to EDCs can alter brain development, affecting reward systems, hormone cycles, eating behavior, and cognition — and how these effects can persist across generations. We also discuss practical strategies to reduce exposure in everyday life, and why age and sex play a critical role in vulnerability.

We wrap with a discussion of EndoScreen.org, a resource Dr. Emily created to translate her research into actionable steps for women and families. If you’re interested in protecting your health, supporting the next generation, and understanding how environmental toxins impact your brain and body, this episode is a must-listen.

Links/Research Articles:

endoscreen.org

https://www.sciencedirect.com/science/article/abs/pii/S0091302222000668?via%3Dihub

https://psycnet.apa.org/record/2021-67755-001

https://psycnet.apa.org/record/2022-66870-001

https://pmc.ncbi.nlm.nih.gov/articles/PMC11698485/

https://pmc.ncbi.nlm.nih.gov/articles/PMC10372431/

https://pmc.ncbi.nlm.nih.gov/articles/PMC11908942/

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Mentioned in this episode:

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Quality relationships are one of the most powerful — and overlooked — drivers of long-term health. In this Goalchella episode, we explore the softer side of wellness with Dr. Lisa, breaking down the science of how relationships impact our physical, emotional, and psychological well-being across the lifespan.

We discuss research showing how supportive friendships, family bonds, and romantic relationships influence everything from immune function to stress resilience. Dr. Lisa shares insights from her work on romantic relationships and marriage, including how happy couples manage conflict, support one another effectively, and strengthen their connection during the good times — not just the hard ones.

This episode dives into concepts like capitalization, gratitude, emotional capital, and sacrifice, explaining why how and why we show up for our partners matters just as much as what we do. We also unpack how everyday stressors quietly erode relationship quality, why daily hassles can be more damaging than major life events, and how couples can buffer stress and even grow stronger through adversity.

We close with an important conversation about friendship — why diverse social networks protect our health, how friendship dynamics differ for men and women, and why maintaining friendships alongside romantic relationships matters more than we think.

If your 2026 goals include deeper connection, this episode will reshape how you think about relationships as a core pillar of wellness.

Links/Research Articles:

https://sites.utexas.edu/realproject/

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​​Wellness isn’t just about workouts, nutrition, or sleep — it also includes financial health. In this Goalchella episode, we explore the softer side of wellness: building money habits that support your goals, reduce stress, and allow you to live a life aligned with your values.

We dive into practical strategies for improving your finances in the New Year, including budgeting, automating savings, and using high-yield accounts and investments to grow your money effortlessly. We also cover common pitfalls, from impulse shopping and carrying credit card debt to letting money drive your emotions, and share actionable tips for curbing these habits.

Beyond everyday habits, we discuss long-term planning for big life goals — weddings, honeymoons, homes, travel, and career investments — and how visualization and prioritization can help you align your money with your dreams. Whether you’re building financial literacy, saving for a future purpose, or simply looking for small tweaks that make a big difference, this episode equips you to approach money as a tool for wellness, not a measure of success.

Links/Research Articles:

https://www.bankrate.com/authors/katie-kelton/

https://www.monarch.com/

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Dopamine plays a central role in motivation, reward, learning, and goal pursuit — and in women, it’s deeply influenced by hormones. In this Goalchella episode, we break down the science of the dopamine system and how fluctuations in estrogen and progesterone across the menstrual cycle shape motivation, focus, mood, and behavior.

We explore sex differences in the dopamine system, why many women feel more driven during certain phases of their cycle, and what research shows about estrogen’s powerful role as a neuromodulator. We also touch on how dopamine function changes during perimenopause and menopause, and why lifetime estrogen exposure may be protective for cognition and brain health as we age.

This episode also tackles one of the most misunderstood topics in women’s health: hormonal birth control. We discuss how hormonal contraceptives influence dopamine, reward sensitivity, learning, and mood — why they aren’t inherently “good” or “bad” — and how individual differences determine each woman’s experience. You’ll learn what signs may indicate dopamine dysregulation, how to recognize patterns across your cycle, and practical steps to advocate for yourself with your healthcare provider.

If you’ve ever wondered why your motivation, focus, or reward-seeking behaviors feel cyclical, this conversation will help you understand your brain — and work with it, not against it.

Links/Research Articles:

endoscreen.org

https://www.sciencedirect.com/science/article/abs/pii/S0091302222000668?via%3Dihub

https://psycnet.apa.org/record/2021-67755-001

https://psycnet.apa.org/record/2022-66870-001

https://pmc.ncbi.nlm.nih.gov/articles/PMC11698485/

https://pmc.ncbi.nlm.nih.gov/articles/PMC10372431/

https://pmc.ncbi.nlm.nih.gov/articles/PMC11908942/

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Mentioned in this episode:

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In this episode, we sit down with Dr. Sam Moore, an expert in female physiology, performance enhancement, and injury prevention. With a master’s in Performance Enhancement and Injury Prevention, a PhD in Human Movement Science, and currently a professor at the University of Oklahoma, Dr. Moore shares her insights into how women can adapt their training to work with their physiology. Discussing the importance of combining strength and cardio, the role of consistency and adaptability in training routines, and the unique aspects of female athlete performance, Dr. Moore emphasizes the value of understanding one’s body, tracking biofeedback, and overcoming the limitations imposed by traditional fitness paradigms. She also delves into managing exercise routines in relation to the menstrual cycle, the concept of athlete availability, and avoiding the pitfalls of fasting and misconceptions around female body composition. This episode provides a comprehensive look at how to foster a dynamic, individualized approach to women’s training and health.

Join us Backstage @ Goalchella: https://drkelsyvickdpt.substack.com/s/backstage-at-goalchella

Dr. Sam Moore's Research: https://scholar.google.com/citations?user=Ml5c1WQAAAAJ&hl=en

Egg Video :) https://www.youtube.com/watch?v=5Ua-WVg1SsA

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Mentioned in this episode:

Join us Backstage @ Goalchella!