The 6/12/25 Program For Bigger, Stronger Legs!


The 6/12/25 program is one of the simplest and most effective hypertrophy training methods ever invented.

The 6/12/25 program is a special type of tri-set where you perform 3 exercises back-to-back for the same body part with 10 seconds rest between sets. Your goal is to perform 6 reps on the first exercise, 12 reps on the second exercise and 25 reps on the third exercise.

Here is what the exact protocol looks like:

The 6/12/25 Training Protocol

  • Perform 6 reps on exercise #1, then rest 10 seconds
  • Perform 12 reps on exercise #2, then rest 10 seconds
  • Perform 25 reps on exercise #3, then rest 2-4 minutes and repeat the series!

The 6/12/25 program is so effective for building muscle mass because it maximizes the three biological triggers for muscular hypertrophy:

  • Mechanical tension
  • Muscle damage
  • Metabolic fatigue

The first exercise let’s you load your muscles with a relatively heavy 6-rep set. This is great for stimulating gains in the fast-twitch muscle fibers and creating a lot of mechanical tension in your muscles.

On the other hand the second and third exercises are perfect for creating a ton of muscular damage and metabolic fatigue. At the end of your 25-rep set on the third exercise you will have one of the best pumps of your life. It will literally feel like your muscles are about to explode!

In my experience the 6/12/25 method is especially effective for training the lower body. The quads and hamstrings are two muscle groups that respond really well to a wider variety of rep ranges AND higher rep ranges.

These muscles have more slow-twitch muscle fibers and grow like weeds on higher rep ranges. If you have never performed 20 or more reps for quads or hamstrings then you are missing out on some serious gains!

In my experience it is extremely important to pick the right exercises for your 6/12/25 tri-sets. This is especially true when it comes to training your legs.

Here is a quadriceps exercise template that you may want to follow:

  • Exercise #1: Any type of squat (front squats, back squats, safety squat bar squats)
  • Exercise #2: Any compound machine exercise (leg press, hack squats)
  • Exercise #3: Any exercise that is easy on your lower back (leg extensions, lunges)

And here is a hamstrings exercise template that you may want to follow:

  • Exercise #1: Any type of leg curl (lying leg curls, seated leg curls)
  • Exercise #2: Any compound hip extension exercise (good morning, stiff-legged deadlifts, back extensions)
  • Exercise #3: Any compound hip extension exercise (good morning, stiff-legged deadlifts, back extensions)

The order of these exercises is really important. They were chosen so that you can train the quads and hamstrings really hard and stimulate a lot of muscle growth without bothering your joints or risking injury.

The bodybuilding coach John Meadows has talked a lot about how you can sequence exercises in your routine to build more muscle and avoid injuries and he is absolutely right. Now let’s look at a couple of sample 6/12/25 leg routines that you can start using today to build bigger, stronger legs.

Note: if you have any trouble reading the routines presented here then check out this article on how to read a training program. Check it out:

6-12-25 Back Squat Routine

  • A1: Back squat (medium stance / heels elevated), 3-4 x 6, 4/0/X/0, 10 seconds rest
  • A2: 45 degree leg press, 3-4 x 12, 3/0/X/0, 10 seconds rest
  • A3: Leg extension, 3-4 x 25, 2/0/1/0, 180 seconds rest
  • B1: Bilateral lying leg curl (Poliquin method / feet neutral), 3-4 x 6, 4/0/X/0, 10 seconds rest
  • B2: 45 degree back extension, 3-4 x 12, 3/0/X/0, 10 seconds rest
  • B3: DB stiff-legged deadlift, 3-4 x 25, 2/0/1/0, 10 seconds rest

Here are the exercise videos: exercise A1, exercise A2, exercise A3, exercise B1, exercise B2, exercise B3.

This is an awesome lower body routine that will shock your body into growth. For the quadriceps portion of the routine you are performing back squats, leg presses and leg extensions. These are classic bodybuilding exercises that even most beginners are familiar with.

Performing 25 reps on the leg extension machine will be difficult but you don’t have to worry about your lower back or balancing the weights so you should be able to push through the pain.

The hamstrings portion of the routine focuses on some simple but effective exercises like lying leg curls, 45 degree back extensions and dumbbell stiff-legged deadlifts. This routine will blow up your quads and hamstrings if you train with enough intensity.

I recommend you perform 3-4 of these tri-sets depending on how you feel that day. If you feel better than Ron Burgundy playing the flute then go ahead and perform 4 total tri-sets. On the other hand if you feel like you are trapped in a glass cage of emotion then stick with 3 total tri-sets.

Now let’s look at a slightly more advanced 6/12/25 lower body routine. Check it out:

6-12-25 Front Squat Routine

  • A1: Front squat (narrow stance / heels flat), 3-4 x 6, 4/0/X/0, 10 seconds rest
  • A2: Machine hack squat, 3-4 x 12, 3/0/X/0, 10 seconds rest
  • A3: Walking DB lunge, 3-4 x 25, 2/0/1/0, 180 seconds rest
  • B1: Bilateral seated leg curl (feet dorsiflexed / pointing out), 3-4 x 6, 4/0/X/0, 10 seconds rest
  • B2: Standing barbell good morning, 3-4 x 12, 3/0/X/0, 10 seconds rest
  • B3: Romanian deadlift, 3-4 x 25, 2/0/1/0, 10 seconds rest

Here are the exercise videos: exercise A1, exercise A2, exercise A3, exercise B1, exercise B2, exercise B3.

This 6/12/25 workout features some more advanced lower body exercises including front squats, walking dumbbell lunges, standing barbell good mornings and Romanian deadlifts. If you are more of an intermediate or advanced lifter I highly recommend you give it a shot.

Once again I recommend you perform 3-4 tri-sets for your quads and 3-4 tri-sets for your hamstrings. If you feel better than Ace Ventura hijacking a monster truck then seize the day and perform 4 grueling tri-sets. On the other hand if you feel like you are moving in slow-motion in the gym then you’re probably better off performing 3 tri-sets per muscle group.

For both of these workouts it’s very important to use the correct rest periods and exercise tempos. They are there for a reason!

The 6/12/25 program is one of the best lower body training methods ever invented. It works for almost anyone who is willing to push themselves in the gym. If you want to turn your chicken legs into tree-trunk thighs then these 6/12/25 leg routines have your name written all over them!

“You are the master of your destiny. You can influence, direct and control your own environment. You can make your life what you want it to be.”

Thank you for reading and I wish you the best of luck in your strength training journey!

Dr. Mike Jansen

Thanks for checking out my site! My name is Dr. Mike Jansen, PT, DPT. I'm the creator / owner of Revolutionary Program Design. My goal is to make RPD the #1 strength training resource available anywhere on planet Earth. If you're from another galaxy then all bets are off! So grab a seat, kick back and relax. There's never been a better time to pump iron or to learn the art and science of strength training program design.

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