My friend and strength coach extraordinaire Alwyn Cosgrove once told me that when choosing a topic for an article to think of what people ask about most often.

Considering Alwyn has an annoying tendency to be right almost all the time, clearly I should start writing more about fat loss.

Some experts want you to believe that losing fat is just a simple math problem: eat less and exercise more. While we we'd all prefer a simpler, more concise approach, anyone who's been at this a while will tell you that there's a lot more to getting lean than just that.

Food choices matter. Recovery matters. And maintaining, even gaining muscle as opposed to losing it, matters big time.

In this article I'm going to divulge a battle-tested fat loss protocol I developed, one that I've used for several years to help athletes and physique competitors lose fat and maintain muscle.

It's effective but also extremely versatile, and can be used in virtually any setting, regardless of space or equipment limitations.

However, it's not easy – and if you apply yourself accordingly, you may catch yourself wondering why the heck you're putting yourself through this.

The answer of course, is that if getting ripped were as easy as Grade 4 math, everyone in junior high and beyond would have a six-pack.

The name "Fat Loss 4" isn't just a catchy tagline. It also represents the most important aspects of this workout formula.

A Fat Loss 4 workout is four exercises, performed back-to-back in a circuit style, for a total of four minutes.

There are two basic components to the FL4 protocol: three strength (local muscle conditioning) exercises and one total-body cardiovascular (central conditioning of the heart and lungs) drill.

skull-crushers

The four exercises making up a Fat Loss 4 (FL4) circuit are:

  1. Upper body pushing or pulling
  2. Lower body quad or hamstring dominant
  3. Torso/core
  4. Cardio drill

The beauty of the FL4 protocol is its simplicity and versatility. You can plug in virtually any exercise you like, provided it fits the category.

That said, I've found that certain exercises seem to work better than others. You'll find some of my favorites later in this article.

How long is a FL4 circuit?

A FL4 circuit consists of four minutes of work with one minute of rest, for a total of five minutes.

Each strength exercise is performed for 30 seconds, with 15 seconds rest between exercises.

For example:

  • Upper body (pushing or pulling) exercise x 30 seconds
  • Rest 15 seconds
  • Lower body exercise x 30 seconds
  • Rest 15 seconds
  • Core/torso exercise x 30 seconds
  • Rest 15 seconds
  • Cardio exercise 90-105 seconds (That's 1:30 – 1:45)

Note: Cardio duration depends on how much you need to recover after performing all three strength movements. The longest rest interval I'll allow is 30 seconds, which would put you at 2:30 when starting the cardio exercise.

Ideally, you'll only rest 15 seconds transitioning from strength to cardio, which would put you at 2:15 when starting the cardio drill (and leave you with 1:45 to do cardio).

Sets and Rest

After you've completed a full four-minute circuit, you'll rest for one minute. We typically perform 2-3 rounds of a given FL4 circuit for a total of 10-15 minutes. (Two rounds is a total of 10 minutes; three rounds is a total 15 minutes.)

Intensity of an FL4 Workout

There are two intensities to consider in the FL4 protocol:

  1. The total intensity of the entire circuit.
  2. The working intensity of each exercise within a given circuit.

During the strength exercises within a circuit, you should be able to complete the entire 30 seconds of work with good form and a consistent, controlled tempo.

On a scale of 1-10 (10 being working very hard), you should be at a 7 or 8 at the end of each strength exercise.

On the cardio exercise, we're after a pace that gets you to about 80% of your max heart rate.

By the time you're about to begin the next round of an FL4 circuit, you should feel mostly recovered. Basically, if you can get out a full sentence without huffing and puffing, you're good to go. But if you're still sucking wind after your 60-second rest between circuits, you need to reduce the intensity of the cardio.

Designing a workout is easy once you understand the formula.

I've found it works well to change the strength movements every 2-3 rounds, although as mentioned earlier, I like to keep the cardio drill the same throughout the workout. So although the strength moves may change, the cardio remains constant.

Here are a few sample FL4 circuits.

FL4 Circuit #1

  1. Push: Push-back push-ups
  2. Lower body: BB front squats
  3. Torso/core: Landmine rotations
  4. Cardio: Treadmill run (Run pace – between a light jog and all-out sprint.)


FL4 Circuit #2

  1. Pull: Compound rows
  2. Lower body: Step-ups (alternate legs)
  3. Torso/core: Stability ball knee tucks
  4. Cardio: Treadmill run (Run pace; between a light jog and all-out sprint.)


FL4 Circuit #3

  1. Push: Dumbbell uppercuts
  2. Lower body: Barbell or trap-bar deadlifts
  3. Torso/core: Dumbbell plank rows (aka Renegade rows)
  4. Cardio: Treadmill run (Run pace; between a light jog and all-out sprint.)


After performing 2-3 rounds of the same exercises, change the strength exercises and perform a new circuit for another 2-3 rounds while keeping the same cardio drill.

Sticking with the same cardio drill helps develop a consistent workout rhythm, while changing the strength moves every so often creates variety while serving to minimize localized muscle fatigue.

What exercises work best to use in an FL4 workout?

The great thing about FL4 is that it's "plug and play." You can insert just about any appropriate upper body, lower body, core, or cardio exercise you like and get great results.

However, there are a few movements I've found work exceptionally well with both my athletes and general fat loss clients. Here are my top five moves to try when designing your FL4 workouts.

  1. Shoulder to shoulder press
  2. Push-ups (any variation)
  3. Standing two-arm cable press
  4. Landmine press and catch
  5. PowerMax 360 Punch

Note: The PowerMax 360 is one of my favorite upper body training pieces.




  1. Barbell bent-over rows
  2. Compound rows
  3. Band alternate arm speed rows
  4. Blast strap or TRX recline rows
  5. PowerMax 360 arm circles (out to in)



  1. Kettlebell goblet squats
  2. Weighted sled or tire drags (forward or backward)
  3. Barbell Zercher or front squats
  4. Barbell or dumbbell reverse lunges
  5. Dumbbell step-ups

Top 5 Core/Torso Exercises

  1. Stability ball plate crunch
  2. Stability ball knee tuck
  3. Barbell rainbows
  4. Dumbbell plank rows
  5. Medicine ball tight rotations


  1. Airdyne bike
  2. Jump rope
  3. Shadow boxing (only if you have some basic boxing/kickboxing ability)
  4. Treadmill
  5. Agility ladder

Note:The exercises above are all either bilateral (two arm or two leg) or alternate limb actions. I've also experimented with unilateral exercises, performing one circuit on the left side and the next round on the right side.

Although this methods works, I've found circuits run smoother with either purely bilateral actions or with alternating limb actions like lunges, where you switch legs on each rep.

I also recommend sticking with compound strength movements instead of smaller, single-joints actions. This should be obvious, but compound strength movements create a better metabolic training response than single joint actions as they involve more muscle mass.

There are four reasons why this protocol works so well for losing fat and keeping muscle:

  1. It's total body. The more muscles you work, the more energy you must use, meaning the more calories you burn both during the workout and for several hours after through Excessive Post Oxygen Consumption (EPOC).
  2. The sequencing creates a cardiovascular effect. FL4 blends local muscle conditioning (through strength moves) with central conditioning (heart and lungs) to create a comprehensive metabolic workout. During any strength exercise, your body pumps more blood to the working muscles. By following an upper body exercise with a lower body exercise and then a torso/core exercise, you're constantly changing where your body must increase blood flow. Doing this creates a cyclic blood flow effect, forcing your body to increase its cardiovascular output. Finishing each sequence of upper/lower/mid-body exercises with a burst of total-body cardio exercise extends this cardiovascular effect even longer.
  3. The sequencing allows for intensity. Along with using your total-body, the other key to maximizing metabolic cost is working at a consistent high intensity. The F4L is sequenced so that when fatigue begins in a specific muscle group, the exercise is switched to train a different group of "fresh" muscles. By the time you return to the original muscle group on the next circuit, it's been several minutes, giving your body time to recover sufficiently.
  4. You won't lose muscle when you're using muscle. Since there's a heavy component of strength training involved in the FL4 Protocol, we haven't seen any losses in muscle size or strength. Although you're not using maximal weights, you are training with higher volumes, another effective way of creating intensity.

I also don't suggest using FL4 as your only training method. Blending it with some basic strength training and bodybuilding helps ensure the muscle you've worked so hard to achieve is maintained while focusing on losing fat. You'll see how this is accomplished in the sample weekly training splits below.

Here's a few sample three, four, and five-day training splits showing how to incorporate the FL4 protocol with other strength and bodybuilding methods.

Three-Day Split

Monday – Push & FL4

  Exercise Sets Reps
A Bench press (dumbbell or barbell) 4-5 6-8
B Shoulder press (dumbbell or barbell) 4-5 6-8
C FL4 circuits 6-8 rounds *

* total of 30-40 minutes

Wednesday – Legs/Hips & FL4

  Exercise Sets Reps
A Deadlifts (Trap bar or barbell) 5-6 4-6
B Single-leg squat (Bulgarian or free standing) 3-4 6-8 *
C FL4 circuits 6-8 rounds * *

* each leg
* * total of 30-40 minutes

Friday – Pull & FL4

  Exercise Sets Reps
A Chin-ups or pull-ups 4-5 6-8
B Single-arm dumbbell row (dumbbell or barbell) 3-4 6-8 *
C FL4 circuits 6-8 rounds * *

* each arm
* * total of 30-40 minutes

Four-Day Split

Monday – FL4 circuit workout

  Exercise Sets Reps
FL4 circuits 9-12 rounds *

* total of 45-60 minutes

Tuesday – Push/Pull strength workout

  Exercise Sets Reps
A1 Bench press (dumbbell or barbell) 4-5 6-8
A2 Bent over row (dumbbell or barbell) 4-5 6-8
B1 Shoulder press (dumbbell or barbell) 4-5 6-8
B2 Pull-ups or lat pulldowns 4-5 6-8
C1 Skull crushers (dumbbell or EZ bar) 3 10-12
C2 Biceps curl (dumbbell or EZ bar) 3 10-12
D Dumbbell farmer's walk 4-5 1 min.

Thursday – FL4 circuit workout

  Exercise Sets Reps
FL4 circuits 9-12 rounds *

* total of 45-60 minutes

Friday – Legs/Hips/Abs strength workout

  Exercise Sets Reps
A1 Deadlift (trap bar or barbell) 4-5 6-8
A2 Stability ball weighted crunch 4 6-8
B1 Lunges or step-ups (alternate legs) 3-4 6-8 *
B2 Band rotations 3-4 15-20 * *
C1 Leg extension 3 10-12
C2 Hamstring curls (seated or lying on Swiss ball) 3 10-15
D Dumbbell farmer's walk 4-5 1 min.

* each leg
* * each side

Five-Day Split

Monday – FL4 circuit workout

  Exercise Sets Reps
FL4 circuits 9-12 rounds *

* total of 45-60 minutes

Tuesday – Push/Pull strength workout

  Exercise Sets Reps
A1 Bench press (dumbbell or barbell) 4-5 6-8
A2 Bent over row (dumbbell or barbell) 4-5 6-8
B1 Shoulder press (dumbbell or barbell) 4-5 6-8
B2 Pull-ups or lat pulldowns 4-5 6-8
C1 Skull crushers (dumbbell or EZ bar) 3 10-12
C2 Biceps curl (dumbbell or EZ bar) 3 10-12
D Dumbbell farmer's walk 4-5 1 min.

Wednesday – Legs/Hips/Abs strength workout

  Exercise Sets Reps
A1 Deadlift (trap bar or barbell) 4-5 6-8
A2 Stability ball weighted crunch 4 6-8
B1 Lunges or step-ups (alternate legs) 3-4 6-8 *
B2 Band rotations 3-4 15-20 * *
C1 Leg extension 3 10-12
C2 Hamstring curls (seated or lying on Swiss ball) 3 10-15
D Sled or tire drag 4-5 30-40 yards

* each leg
* * each side

Friday – FL4 circuit workout

  Exercise Sets Reps
FL4 circuits 9-12 rounds *

* total of 45-60 minutes

Saturday – FL4 circuit workout

  Exercise Sets Reps
FL4 circuits 9-12 rounds *

* total of 45-60 minutes

Is the FL4 protocol the only method of losing fat while keeping the muscle? Absolutely not! But in my business it's proven to be a safe and effective way to get virtually any client in record shape, fast.

The beauty of FL4 is its elegant simplicity. In my experience, when clients can easily wrap their heads around what they're being instructed to do and why, they "commit" more and as such, get superior results.

On the other hand, excessively complex systems filled with pseudoscientific strength training jargon just yields the dreaded "deer in the headlights" look and subsequently, sub-optimal results.

This powerful fat loss weapon is now locked and loaded in your training arsenal. All you've got to do is use it!