Lead Image: Aaron Hallett, Fivos Photography

Here's what you need to know...

  1. Fasted cardio can strip off extra body fat, but also a lot of muscle if you're not careful.
  2. Muscle loss from cardio can be brought to a stop with the right kind of fat-loss workout and the right kind of carefully-timed workout nutrition.
  3. Dr. Lonnie Lowery has tested this method successfully, both in the lab and on the bodybuilding stage.

Cardio has become a bad word. And rightfully so. Traditional, long-duration cardio is associated with muscle loss, strength loss, metabolism damage, hormone disruption, and recurring injury. It can even increase anxiety and trigger cravings and overeating.

What's more, long-term studies show that frequent cardio simply stops working as the body adapts to it. You have to keep increasing the duration and frequency or fat loss will simply stagnate. After years of cardio, studies show that fat gain and increases in waist size occur in most runners, even if they increase their frequency. Result: the prototypical skinny-fat jogger.

So why do most physique competitors like bodybuilders and Figure athletes do cardio? And why do they run the risk of even more problems by doing it fasted, often first thing in the morning on an empty stomach?

Because, for rapid fat loss before a physique show, it works. And a competitor is often willing to lose some muscle and suffer the other drawbacks of excess cardio because he or she is panicked. A looming deadline to stand on a stage nearly naked and have your body judged can have that effect. And many of these competitors can often get away with cardio, at least in the short term, because they're using drugs.

But there is a better way, a smarter way that can triple fat loss from cardio while at the same time halting all catabolism (muscle loss). The answer is semi-fasted cardio. But not just any form of it will work.

Built Like a Lifter, Not a Runner

"I don't want to look like a wrestler or a Crossfitter," Dr. Lonnie Lowery said. "I want to look like a bodybuilder. That's why I came up with this method for fasted cardio."

Dr. Lowery experimented with an early version of this protocol while preparing for a bodybuilding show. The nutrition professor and research scientist didn't want to take any chances. He needed every ounce of muscle for the stage, but he also needed to get ridiculously shredded. His solution was extreme, but it gave him exactly what he was looking for: maximal fat loss and full muscle retention, something that's nearly impossible to achieve when dieting down for a bodybuilding show.

"I know this method is crazy. It's not for everyone. But hey, it was competition time. I wasn't playing games," he said.

Dr. Lowery is a natural ectomorph, growing up a skinny, scrawny kid. His body doesn't "want" all that extra muscle, and he has to use everything in his intellectual arsenal to build it and, most importantly, keep it. After his mass phase, Lowery found himself sitting at a too-thick 20% body fat. It was time to do something drastic: fasted cardio. But this time, Lonnie had a secret weapon.

Attack Body Fat When It's Vulnerable

The premise is simple: Every morning Lowery woke up early and performed an hour of fasted "cardio." That means it's done before he consumes any type of solid food.

Why? Because body fat is vulnerable at this time. It's weak because your insulin level is at rock bottom in the morning. Fat is left unprotected. This is the ideal time to maximally oxidize fat with a cardio-type of activity, tripling fat mobilization over already high resting values. (1) The problem? Too much high intensity cardio can eat up muscle tissue. The goal here is to preferentially burn fat, not muscle.

Lowery has a unique method to avoid muscle loss while draining fat stores. Instead of steady-state running or interval-style sessions, he uses incline walks on a treadmill lasting about an hour. He calls this "non-panting cardio," though he adds that it's not "real" cardio in the technical sense of the word.

It seems easy, and the actual workout is, but performed in a fasted state with the addition of caffeine and one other tactical supplement, this method can rip off excess body fat while protecting lean body mass. Just an important, this low to moderate intensity allows him to save most of his energy for his strength-training session later in the day.

Secret Weapon and Advanced Tactics

Lowery has been using this style of cardio for years. When he cuts 25 pounds of weight for a bodybuilding show, typically only three to five pounds come from muscle tissue, which is quite good. But what if he could prevent all muscle loss? He'd walk onto the stage with three to five pounds more muscle. At very low body fat, that has a dramatic visual impact. And it could mean the difference between first and fourth.

Lowery has tried several methods over the years to maximize this strategy, including pre-cardio glutamine and a small amount of whey protein powder. The results were hit and miss. He notes, "Whole proteins consumed in the middle of a workout might mess up fat mobilization and fat burning."

The final solution was this: a serving of a unique di- and tripeptide complex that's transported – unaltered, requiring no further breakdown – directly into the bloodstream during the morning workout. In other words, Mag-10®.

The Test

It's not comfortable performing cardio with a big tube in your mouth, but Dr. Lowery was determined to test out this new protocol. There were a couple of things he had to know.

"I went into the lab early one morning, hooked myself up to the metabolic cart and tracked my fat oxidation as I sipped Mag-10," Lowery said. "I can't tell you how pleased I was to see the results in real time."

Lowery said that respiratory exchange ratio (RER) started at 0.75 – about 80-84% of all calories burned from fat stores, which is great. Anything below an RER of 0.80 indicates a preponderance of fat burning. After drinking the first third of the mixture in minute 15, his RER remained 0.75. Good so far. After drinking the next third at minute 30, his RER was 0.74 – just as good or slightly higher fat oxidation. A final swig at the 45-minute mark and Lowery's RER was 0.75! Perfect.

"These numbers confirm my theoretical training and literature reviews," noted Lowery. My fat burning remained in high gear during my optimized aerobic session, while my muscles were fully protected! This is a prime example of tactical nutrition."

The Mag-10 Method, Disclosed

Intrigued? Here's exactly how Dr. Lowery uses this powerful strategy:

  1. Before bed, place a bottle of water and half a caffeine tablet (100 mg) on your nightstand. Set your alarm for 10 minutes before you want to get up.
  2. When the alarm goes off, take the caffeine tablet and hit snooze. Doze back off if you can. Dr. Lowery calls this his "caffeine snooze." Ten minutes later, when the alarm goes off again, get out of bed, mix up one serving of MAG-10 in water, and find a treadmill.
  3. Set the incline of the treadmill at 4%. Start walking at 3 MPH. The whole workout should be kept a just-below panting level. Heart rate should never exceed 120 BPM (beats per minute) for younger guys, and should be closer to 110 or 115 BPM for older men. Lowery is in his 40's and shoots for around 115 BPM.
  4. Ten to 15 minutes after exercise has begun, drink one-third of the MAG-10. Halfway through, drink another one-third. About fifteen minutes before finishing the workout, finish it. The idea is to spread MAG-10 intake evenly throughout the workout session. You could also do this in halves: half the drink after beginning the session, half 15 minutes before finishing.
  5. Eat breakfast as soon as you're finished.
  6. Lift as usual later in the day utilizing a good workout nutrition protocol. That means once again manipulating insulin: jacking it up this time and lifting weights hard in that anabolic state. Plazma™ would be ideal here.


Equipment Selection: Dr. Lowery usually uses a treadmill, but he does use an elliptical or stationary bike on occasion. Same rule applies: Keep it non-panting. What if you don't have access to a cardio machine? No worries, just go for a fast walk. Lowery also suggests alternating between a light jog and a walk. If you're at a school track, walk a lap, jog a lap, repeat. You can also use a weighted vest. But remember, this is not "cardio" in the usual sense. No sucking wind.

Progression of Exercise Duration: When preparing for a bodybuilding competition, Lowery will begin his cutting phase with 45 minutes of cardio using this method. ("Twenty minutes is a waste of time," he said.) As the show nears, he'll move up to 60 minutes on average, sometimes a little longer.

Progression of Incline: As the excess fat burns off and the show gets closer, Lowery becomes more aerobically fit. He'll bump the treadmill incline from 4% to 7%, and finally to 10% as the competition nears. Again, keep this at a non-panting level, below 120 BPM.

Progression of Speed: There isn't one. This is a walk, not a run (unless you're using the walk/jog method).

Weekly Schedule: Lowery uses this method six days per week when preparing to step onto the bodybuilding stage.

Too Much for You? Or Just What You Need?

Extreme? Time consuming? Maybe. But if your goal is pure fat loss and full muscle retention, then Dr. Lowery has perfected the strategy to achieve it. All you need is a treadmill, some cheap caffeine tablets, a container of Mag-10® and the desire to carve your ultimate body.

Set the alarm.


  1. Jensen, M. Fate of fatty acids at rest and during exercise: regulatory mechanisms. Acta Physiol Scand. 2003 Aug;178(4):385-90.