Welcome to your modern fitness daily news report! Every weekday, we break down the trending fitness news, tips, and insider scoops to keep you informed. Each read will be under 3 minutes so that you can stay shredded and thumb through no-nonsense fit-quips. Thanks for reading!
TODAY’S LEVEL UP:
Coach's Corner: The Interference Effect: Does Cardio Really Kill Your Gains?
Supplement Spotlight: Taurine — A Promising Amino Acid With More Hype Than Proof
Myth or Real: "Cardio burns muscle."
Question: "Should I do my cardio before or after lifting?"
Fit Trivia: Which medical student training 45 minutes a day on his lunch break broke the four-minute mile?
The Interference Effect: Does Cardio Really Kill Your Gains?
Every gym has a guy who won't do cardio because it'll "eat his muscle." He's referencing something real — researchers call it the interference effect — and he's wildly overstating it.
What the research actually found: Studies going back to the 1980s showed that men doing concurrent endurance and strength training gained less strength and size than men doing strength training alone. The proposed mechanism involves the two types of training signaling partly competing adaptations inside the muscle. That finding is real, and it's been replicated.
What gets left out: The interference effect shows up most clearly under specific conditions: high-volume, high-intensity endurance work — think five or six hard running sessions a week — performed close in time to lifting, in already well-trained lifters, with running in particular. Scale any of those down, and the effect shrinks fast. In the amount of cardio a man over 40 realistically does for health — two or three moderate sessions a week — the measurable impact on muscle and strength is small to negligible.
And the trade is heavily in cardio's favor. Aerobic fitness is one of the strongest predictors of how long and how well you live. Giving that up to protect a hypothetical fraction of a pound of muscle is a bad deal at any age, and a worse one after 40.
How to structure it so the two get along:
Separate them when you can. Ideally, lift and do cardio on different days, or at least 6+ hours apart on the same day.
Lift first if they're in the same session. You want your best quality work going into the stimulus that's hardest to produce.
Choose lower-impact modes. Cycling, rowing, the elliptical, and incline walking interfere less with leg training than running does, and they're friendlier to knees and hips.
Keep most of it easy. 150 minutes a week of moderate work gets you the large majority of the health benefit, and easy-intensity work barely competes with lifting at all.
Don't stack hard leg day and hard intervals back to back. That's where men actually feel the interference — as accumulated fatigue, not as lost muscle.
Train both. Just don't schedule them like enemies.
Supplement Spotlight: Taurine — A Promising Amino Acid With More Hype Than Proof
Taurine got a wave of attention after a 2023 animal study suggested taurine levels decline with age and that supplementing extended lifespan in mice. It's a genuinely interesting compound. It is also a good case study in how far ahead of the evidence a supplement can get.
Here's what it does: Taurine is a sulfur-containing amino acid — technically a "conditionally essential" one, since your body makes some and you get the rest from meat, fish, and dairy. It's highly concentrated in heart, muscle, and brain tissue, where it's involved in calcium handling, cell hydration, and antioxidant defense. On performance, the human research is modest and mixed: some small trials report slight improvements in endurance or reductions in muscle soreness, others find nothing. On aging, the headline work is in mice, not men — the human data is observational, and an association between higher taurine levels and better health is not evidence that swallowing more of it changes anything. Treat this one as promising and unproven.
How to take it: Studies typically use 1–3 grams per day, often taken 60–120 minutes before training when the goal is performance. It's cheap, mixes into water, and has no meaningful taste. It's also worth noting that a normal omnivorous diet already supplies a fair amount, so the marginal benefit for most men is probably small.
Worth knowing: taurine appears well tolerated at these doses in the available research, though long-term safety data is limited. If you have kidney or liver disease, take lithium, or are on blood pressure medication, check with your doctor first. And it's worth separating taurine from energy drinks — the effects people attribute to those cans are mostly the caffeine and sugar.
We recommend taurine as a low-cost, low-risk experiment rather than a staple — and keeping your expectations firmly attached to the human evidence rather than the mouse headlines.
FROM RYAN’S DESK
Progress creates momentum, and momentum makes the next step easier. One workout leads to another. One good meal leads to another. One small win reminds you that you're capable of more. Don't underestimate what happens when you stack enough wins together. Be the guy who keeps moving forward, even when the progress feels small. That's how big changes begin.
Myth or Real: "Cardio burns muscle."
Mostly myth, at least as the phrase is usually meant.
Your body doesn't reach for muscle protein as a preferred fuel during a 40-minute bike ride. It runs on stored carbohydrate and fat. Meaningful muscle loss requires a different set of conditions: a large calorie deficit, not enough protein, no resistance training, and often very high training volume on top of all three. Cardio alone isn't the villain in that list — it's usually just the one that's easiest to blame.
Where men do lose muscle while doing cardio, the cause is almost always under-eating and under-lifting. Ultra-endurance athletes who look wasted got there through enormous training volume plus chronic energy deficit, not because cycling is catabolic.
The protection is straightforward and you probably already know it: keep lifting 2–3 times a week, hit 0.7–1.0 grams of protein per pound of bodyweight, and don't run an aggressive deficit for months on end. Do those three and you can do a lot of cardio without losing anything.
Question from Our Readers: "Should I do my cardio before or after lifting?"
If both have to happen in one session, lift first — with one exception.
The logic is about quality. Strength and muscle adaptations are the harder stimulus to produce and the more sensitive to fatigue, so they should get your freshest effort. Doing 30 minutes of intervals and then trying to squat well is a reliable way to make the squats worse. The reverse costs you much less: easy cardio performed on tired legs is still perfectly good easy cardio.
The exception: if improving your aerobic fitness is your actual priority right now — you're training for an event, or your VO2 max is the number you're chasing — flip it and do the hard cardio first. Whatever matters most goes first.
A short 5–10 minute warm-up on a bike or rower before lifting is not "cardio first" in this sense and is generally a good idea.
And the best answer, when your schedule allows: separate days. Both get your full attention, and neither has to be the leftover.
Our Picks: Supps We Actually Use
Some of our coach’s favorite supplements:
Creatine (Travel Packs) - $36
Add this to your water in the morning or in your post-workout shake. Creatine is one of the few supplements that has a mountain of data proving its benefits. Don’t miss out on it!
A great way to hit your protein goals. Don’t rely on a protein powder alone, but add it as a post-workout shake or midday shake to increase your protein intake and hit your protein goals. Remember, high protein equals higher muscle and higher satiety.
Replenishes essential electrolytes. Use this if you sweat a lot, do intermittent fasting, or go on long-distance walks, hikes, or runs.
We are a proud partner of Thorne Supplements! We are affiliated and use these products. We may receive commission from your purchase.
Fit Trivia: Which British medical student — fitting in roughly 45 minutes of training a day around hospital rounds, with none of the volume a modern distance runner would consider adequate — became the first man to run a mile in under four minutes, clocking 3:59.4 at Oxford's Iffley Road track in May 1954?
Answer: Sir Roger Bannister! His record stood for just 46 days before John Landy broke it — which is arguably the better story. Once men knew it was possible, dozens did it, and the four-minute mile turned out to be a psychological wall more than a physiological one.
Ryan Engel, Intl. Fat Loss Coach
Ryan is a leading fitness coach and one of the most known professionals in the space.
He specializes in Body Recomposition and visual body aesthetics and has reached millions worldwide with his powerful messaging. He brings a unique, non-nonsense, yet sophisticated approach to body change.
Publisher: Ryan Engel
Editor: Michael Pender
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