Muscle power, not strength, predicted who lived and who died.

A 22-year cohort (3,889 adults) showed 5–7x mortality risk for those with low relative power.

Strength didn’t even reach statistical significance.

🧵 Here's the breakdown: Study: Araújo et al., Mayo Clin Proc 2025
rPOW: HR = 5.88 (men), 6.90 (women)

rSTR: Not significant

Power improved C-index, NRI, IDI

Kaplan-Meier curves: steeper drop in survival for low power

Many people still think creatine is risky.

A new study just reviewed: • 685 clinical trials
• 28.4 million adverse event reports
• 129,000+ social media posts

And found…
Creatine is as safe as placebo.

Here’s the breakdown: Side effects in clinical trials:
• 13.7% of creatine studies
• 13.2% of placebo studies

At the participant level:
• 4.60% (creatine)
• 4.21% (placebo)

→ No statistical difference

Muscle mass used to be central to aging research. Then it wasn’t. But another study using D3-creatine shows: the link between mass and function was always there—we just weren’t measuring it right. A thread: Sarcopenia was defined as loss of muscle mass—not strength. But studies using DXA and BIA showed weak associations. So strength took over.

🚨 Can protein intake prevent muscle loss during immobilization? Two new studies suggest it might not be enough. A thread 🧵👇

Study 1: 33 young men immobilized for 3 days. They ate either:
High protein (1.6g/kg/day)
Low protein (0.5g/kg/day) Almost no protein (0.15g/kg/day)

Results? All groups lost 2-3% muscle volume and muscle protein synthesis (MyoPS) dropped 26-30%—no difference between diets. 😨

Study 2: 12 adults immobilized for 14 days.

🚨 Why Checking B12 Alone Isn’t Enough 🚨

A normal B12 test result doesn't always mean you're in the clear! Total serum B12 doesn't reflect active levels—functional tests like MMA & homocysteine are key. Learn why comprehensive testing matters: Many people with B12 deficiency are misdiagnosed because they only get a serum B12 test—which can miss real deficiencies. Let's break it down 👇

Losing muscle with age isn't inevitable. Sarcopenia, or age-related muscle loss, can be slowed—even reversed—with resistance training. Here’s how exercise impacts muscle stem cells (satellite cells) and keeps you strong. 🏋️‍♂️👇 Sarcopenia leads to a decline in type II muscle fibers, which are crucial for strength & power. Research shows that satellite cells—responsible for muscle repair—also decline with age, reducing muscle regeneration.

🚨 Think you’re too old to lift weights? Think again! 🚨
A new study shows that progressive resistance training can reverse muscle loss, improve mobility, and enhance quality of life—even in adults over 80! 🏋️‍♂️💪 Let’s dive into the science. 🧵👇 1/ Sarcopenia—the age-related loss of muscle—leads to frailty, falls, and a loss of independence. But research proves resistance training can reverse it. 🔥

2/ A new meta-analysis found that machine-based strength training improves leg strength, mobility, and endurance. 📈

Genotype Doesn’t Always Predict Phenotype—Here’s Why

Your genetics don’t dictate your muscle function or sarcopenia risk as much as you might think. The ACTN3-R577X study reinforces a key principle in genetics: genotype ≠ phenotype.

Let’s break it down. 🧵👇 The ACTN3-R577X polymorphism is one of the most well-studied genetic variations in muscle function & athletic performance. It affects α-actinin-3, a protein in fast-twitch (type II) muscle fibers, which are key for explosive strength & power movements.

🚨 What Happens When You Stop Moving? 🚨

Most people know exercise is important. But short periods of inactivity can cause major declines in your health.

👇 Just two weeks of reduced steps can lead to this 👇 When you reduce your daily steps, even briefly, here’s what happens:

❌ Insulin Sensitivity Drops – Down 44%, increasing diabetes risk.
❌ Muscle Mass Shrinks – Young adults lose ~2.8% of leg lean mass.
❌ Strength Plummets – Losses of 6-9% in 14 days.

Resistance training is the best intervention for sarcopenia, but are we prescribing it effectively?

Three key studies help answer this. 🧵 📌 Study 1: "Effects of Resistance Training in Healthy Older People with Sarcopenia: A Systematic Review and Meta-Analysis" (Chen et al., 2021)

Focuses on the overall impact of resistance training in older adults with sarcopenia.

New research highlights creatine + resistance training as a key strategy for preserving muscle & cognitive function in aging adults.

Here’s what Bonilla et al. (2024) found about optimal dosing & benefits of creatine for longevity. 🧵 @dabonillao @ExphysPhD @darrencandow @DrCreatine 📌 Aging & Sarcopenia = Muscle & Cognitive Decline
We lose ~3-8% of muscle per decade after 30, leading to:

✅ Increased fall risk
✅ Metabolic slowdowns
✅ Cognitive decline

Creatine + resistance training is a science-backed solution.

Have you read "Understanding the Consequences of Fatty Bone and Fatty Muscle"?

Are you curious how fat infiltration impacts your muscle strength and quality?

Here’s a thread. 🧵 Did you know fat can infiltrate muscle? This process, called myosteatosis, is central to sarcopenic adiposity—a condition where fat disrupts muscle strength and function.

Aging often leads to reduced physical independence, creating a vicious cycle of inactivity, muscle loss, and frailty. Addressing these declines through exercise and nutrition is key to preserving function and quality of life.

Here’s how: Muscle aging is influenced by several factors:
•Mitochondrial dysfunction
•Increased inflammation (inflammaging)
•Fibrosis of connective tissue
•Anabolic resistance
•Reduced muscle mass
These changes are interconnected but can be mitigated.

Mitochondria, Sarcopenia, Aging and Exercise.
How are these related and what can we do?
A 🧵 Healthy mitochondria:
•ATP is produced efficiently through oxidative phosphorylation.
•ROS (reactive oxygen species) are managed by antioxidants like catalase & superoxide dismutase (SOD).
•Fusion & fission maintain balance, repair damage, & recycle dysfunction via mitophagy.

Strength training doesn’t have to be complicated. Here’s a breakdown of evidence-based principles for strength and hypertrophy gains based on research 🧵

https://twitter.com/jploenneke/status/1874612733221720542

Maximal Strength = Heavy Loads
For maximal strength, heavy loads (e.g., >80% of your 1RM) are essential. This optimizes neuromuscular adaptations like motor unit recruitment & force production.

Heavy beats light here (Schoenfeld et al., 2017)

Sarcopenia—the loss of muscle mass and function—can occur due to aging or disease. While these processes share similarities, they differ in their underlying mechanisms and clinical outcomes. Let’s dive into what we know and why one size does not fit all. 🧵 Sarcopenia has evolved from being defined simply as low muscle mass to a condition that also includes reduced muscle strength and function. This shift highlights its role not just as a physical problem, but as a systemic issue with broad health implications.

Can we measure how well your body is aging? Maybe so, and science just made it simpler. 🧵

1️⃣ A global study identified 14 biomarkers to track biological age—how well your body is functioning, not just your years.

h/t @reshmaamerchant @mackinprof @KostasProko @reshmaamerchant @mackinprof @KostasProko 2️⃣ How were they chosen?

460 experts from 25 countries.
A 3-round Delphi method study evaluated biomarkers based on:
✅ Scientific reliability
🛠️ Practicality
💰 Affordability
🔍 Sensitivity to interventions.

Can muscle power help older adults live longer, regardless of their weight? A study explored the 'Fat but Powerful' paradox and its impact on mortality. Here's what they found: 🧵 The study followed 2,563 older adults (65–91 years) over 9 years. It assessed muscle power (sit-to-stand tests) and adiposity (BMI, waist circumference, body fat %, fat index).

Participants were classified into 4 groups:
Lean + Powerful
Fat + Powerful
Lean + Weak
Fat + Weak

1/ Creatine might be a game-changer for chronic liver disease (CLD) and fatty liver (MAFLD). Did you know creatine production depends on both the kidneys & liver?

When liver function is impaired, creatine synthesis drops, with major metabolic consequences. 🧵 @scottisaacsmd @DrCreatine @darrencandow 2/ Here’s how it works:

Kidneys produce guanidinoacetate (GAA) using AGAT. GAA travels to the liver, where GAMT converts it to creatine. Liver dysfunction disrupts this process, reducing endogenous creatine.

Sit-to-Stand Power (STS Power) for Sarcopenia Screening in Primary Care

Why Sarcopenia Matters
Sarcopenia (loss of muscle strength/power with age) affects ~10% of older adults and increases the risk of falls, hospitalizations, and mortality.
Primary care can change that.

A 🧵 We know about the ease and predictive power of handgrip testing. But what if an injury prevents this test?

Sit-to-Stand Power (STS Power) might be the solution. Here’s why. 🧵

1/ 🧵 Lifetime exercise vs. starting later: Can you still benefit from exercise if you didn’t start young?

Let’s explore the impact of physical activity on arterial stiffness and cardiovascular health, as highlighted in a 2024 review in the Journal of Clinical Hypertension. 👇 2/ Arterial stiffness, a predictor of cardiovascular disease and mortality, can be reduced with regular exercise. But does it matter when you start?

The review emphasizes that lifetime physical activity has the most profound effects on maintaining flexible, healthy arteries.