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Core Knowledge


The Simple Guide to Core Performance Training Phases

Dave Cruz


Core Performance training programs progress through a series of five 3-week phases.

How it Works

Don’t think of the phases as 1 through 5 and then you’re done, but rather a continuous cycle in which you’re always progressing and challenging your body in new ways. Another way to think of it: You’ll continually switch gears, from working on your foundation to focusing on strength, stability, and so on.

If you were constructing, say, a house, you might lay the foundation and be done with it, but your body’s different. You need to continually develop all elements that contribute to your performance, and that includes rebuilding your foundation often. At other times, you may need to focus more on strength, power or endurance.

Each of these phases is dependent on another. Remove your sturdy foundation and it becomes increasingly difficult to produce power. Stop working on mobility and you have less room to build strength. If this balancing act sounds more like an exercise in science, that’s because it is. Exercise physiologists refer to it as “periodization,” which basically means a planned and progressive method of changing your workouts.

EXOS specialists have spent years developing this system, testing it and refining it with elite athletes and top performers from all walks of life. So if you’re following a Core Performance training program, all you need to know is that continually cycling through these phases addresses all of your body’s needs, allowing you to continually improve, while reducing your risk for injury.

Phase 1: Foundation

This phase introduces you to key movements, or exercises, that you’ll perform throughout your program, such as squats, deadlifts, chops, lifts and lunges.

Think you already know these moves? Even elite athletes need to review and refine these exercises since they’re essential in laying the groundwork for greater gains in mobility and stability. Practicing these lifts will also help address any asymmetries you may have developed.

Discrepancies in mobility and stability are common. Many athletes have less mobility in their throwing shoulder, for example, than their non-throwing shoulder. But it’s important to balance your body to avoid one side picking up slack for the other, since this can result in injury and decrease performance.

Depending on your program, you’ll notice the number of repetitions prescribed for your workouts begins to either increase or decrease during this phase. You’ll want to adjust the weight accordingly, using heavier loads when performing fewer reps and lighter loads for high reps.

Phase 2: Get Stable

This phase ramps up the intensity of your training to help prepare you for the strength building phase. The focus is on taking the quality of movement you gained in the foundation period and making those movements more challenging.

The movements may or may not change depending on your program, but you’ll perform fewer repetitions, so use heavier weights to challenge your muscles, and focus on technique.

Phase 3: Get Strong

You’ll decrease the number of repetitions you perform yet again in this phase and really challenge yourself with the amount of weight you lift.

If you’re performing a program with a lifestyle goal (lose weight, reduce pain, etc), you may notice that you’re performing a lot of “isolateral movements,” meaning using one leg or arm at a time (e.g. single-leg Romanian Deadlift) or alternating arms or legs (e.g. alternating bench press). This helps you build both strength and symmetry throughout your body.

If you’re on a sports program, you’ll do a lot of movements on two legs or two arms, giving you a solid base to push your strength limits.

Despite the increased emphasis on using heavier loads to improve strength, keep in mind that quality of movement is critical, so focus on using proper technique in every move you do.

Phase 4: Work

In this phase, you’ll take the strength you’ve just gained and apply it in training sessions that test your stamina.

You may notice that the number of repetitions you do increases, so the length of your sets becomes longer. This strategy builds muscular endurance and conditions you to a higher volume of work. It may also stimulate your metabolism and muscle growth.

During this phase, both lifestyle and sport programs focus on “isolateral work,” or movements that challenge your limbs independently, which helps troubleshoot strength imbalances and builds symmetry.

Phase 5: Get Powerful

Power may be the most underrated element in training for people who have no interest in sports. You might think, What do I need power for? But research has shown that power fades fast as you age and significantly impacts whether you wear down early or stay active well into your golden years.

The payoffs of power are more obvious for athletes. Building a more powerful, explosive body will help you make sharper moves, burst through holes and leap higher.

If you’re following a sport program, you’ll drop the repetitions and work on your “rate of force development,” meaning you’ll perform the movements fast. But don’t sacrifice form for speed. Just work on accelerating the loads and exhibiting your strength in less time.

If you’re following a lifestyle program, your reps will drop, as well, and the intensity of your training will increase.

Tags: Power, Strength, Build Muscle, Mobility, Stability, Training


  1. Craig Friedman, Director of Methodology, EXOS