Strength numbers

Volt's guide to strength numbers + challenge sets


One key ingredient that makes Volt training so safe and effective is the personalized loading recommendations for each athlete. Volt's intelligent training technology evaluates each athlete's strength levels, then uses that data to calibrate the loading for almost every movement in the athlete's training program. To evaluate an athlete's strength levels, Volt uses Strength Numbers: the most weight they can lift in each of the 3 Volt base lifts. And to keep things easy for coach and athlete, Volt automatically prompts athletes to find their Strength Numbers during certain workouts, in special testing sets called Challenge Sets.

Since this is one of the most important aspects of every Volt training program, we put every question we receive regarding Strength Numbers and Challenge Sets in one spot (this article), and answer each one in detail. 

1. What are strength numbers?

Strength Numbers are a measure of how much an athlete can lift (with good technique) in the 3 Volt base lifts: the hang clean, back squat, and bench press. If you're familiar with strength training programs, you might know how to find your 1-rep or 5-rep maximum (1RM or 5RM) in a given exercise, and that's exactly what Volt Strength Numbers are. Volt takes the number of reps an athlete is able to complete of a given movement and converts it into a projected 1RM, which we use to recommend loading for other movements in the training program.

Why does it work this way? Because finding 1RMs for every movement in your Volt program would take forever. Instead, Volt takes a measure of your lower-body strength (back squat), upper-body strength (bench press), and explosive strength (hang clean) and makes recommendations based on those numbers. This method has been tested and proven by 100,000+ athletes and coaches in the Volt Family, and it's extremely effective.

2. Why is precise loading important?

The amount of weight an athlete lifts in a given exercise (and the specific number of reps and sets completed, and the specific interval of rest between exercises) dictates precisely what training adaptation the body will undergo. Volt scientifically varies the weight lifted and number of reps and sets performed in order to produce the most optimal adaptations for sport performance at a specific time.

For example: if you back squat 85% of your 1RM for 3 reps, it trains your muscles to recruit a greater number of muscle fibers in order to produce greater amounts of force. But squatting 65% for 10 reps trains your muscles to develop an entirely different adaptation (in this case, hypertrophy, which causes the muscle fibers to grow larger). 

Training for a specific sport requires a variety of training adaptations to take place in the body, all of which require precise and unique training protocols. Strength Numbers help ensure that athletes are lifting exactly the right weight, at exactly the right time. 

3. What if my athletes don't have strength numbers?

Even though Strength Numbers are important, there's a lot that goes into each Volt program that makes it effective. Other variables, like the movements in a given workout and the rate at which movements progress in terms of complexity, guarantee that athletes will see results, even without Strength Numbers. If your athletes don't have Strength Numbers, they will simply see blanks where the recommended loading would be.

While this isn't ideal, it's not the end of the world. Will your program be as effective if athletes don't have prescriptive loading data? No. Will your program still work? Yes.

Even if athletes estimate how much weight to lift in each movement, you will still see improvement. But to get the very best results, you will want to find their Strength Numbers. Frequent retesting of Strength Numbers means that your program will dynamically adjust as athletes grow stronger, following the principle of progressive overload. With no Strength Numbers, your athletes will have to choose their weights manually. And chances are the weights they choose for themselves will not be as accurate or effective as the weights prescribed based on your current strength levels.

If an athlete has a barrier to finding Strength Numbers—an injury, or other issue that prevents them from executing the three specific lifts—see question #8.

4. How does an athlete find initial strength numbers?

There are two ways an athlete can find their initial or baseline Strength Numbers: 1) perform a maximal testing session, or 2) wait until a Challenge Set is recommended in a workout.

If you choose to test your athletes outside of Challenge Sets, it's important to remember that athletes do NOT need to find a "true" 1RM, or absolute maximum, to get Strength Numbers. Volt uses a formula to calculate a projected 1RM based on how many reps an athlete can perform. For example, if an athlete can squat 150 lb for 8 reps, we estimate they could squat about 190 lb for 1 rep. For athletes new to lifting, we recommend using a 3-5RM protocol to test athletes (save true 1RM testing for experienced lifters). We also recommend capping any max testing at 10 reps maximum, as 1RM projections get less accurate with a higher number of reps performed.

If you choose to wait until a Challenge Set is recommended (usually in the last week of Strength Capacity, Strength, and Max Strength training blocks), athletes will be prompted to test right from their workout. A Challenge Set is indicated with a yellow bar and instructions for athletes to complete as many reps as possible (with good technique) of the given movement.

5. Is there a step-by-step guide to finding strength numbers for the first time?

Step 1: WARM UP.

Volt recommends athletes warm up before every workout, and especially before attempting heavy lifts. Spend 3-5 minutes raising the heart rate (jogging, jump rope, etc.) then 5-10 minutes performing a dynamic full-body warm-up. We recommend using the same Dynamic Warm-up you use before a regular Volt workout.


The hang clean is the most complex and taxing movement of the 3 base lifts, so test it first for best results.

Note: Athletes do NOT need a spotter for this lift. Check out this article on spotting guidelines to learn more.


Perform 2-3 lighter "warm-up sets" before the weight begins to feel challenging for the number of reps you're aiming for (between 1 and 5 is recommended). After each warm-up set, add weight until the bar starts to feel heavy. How much you add depends on current strength levels, training experience, and comfort in the hang clean. The goal of warm-up sets is to progress to an appropriately challenging weight to begin your "working sets."

Novice lifters can start with an empty bar; experienced lifters should start their warm-up sets with some weight. 


The goal of your working sets is to progress you toward a weight you can only lift for 1-5 times with good form. Aim to reach your maximum in about 4 sets. Rest 2-4 minutes between sets. Athletes familiar with max testing can progress until they can complete 1 rep with perfect form at a given weight, but not 2 reps.


Perform the same testing protocol to find 1-5RMs in the back squat and bench press.

Note: We recommend that ALL athletes use a spotter when attempting heavy loads in the squat and bench. See this article on spotting guidelines for specific guidelines on spotting these movements.

REMEMBER: you do not NEED to perform exactly 5 reps or exactly 1 rep to find your strength numbers. Volt's algorithm will calculate your estimated maximum based on the data you input. It is much better to perform 4 perfect reps safely than to attempt a 5th rep with broken form.

6. Are there any resources for testing my athletes?

Yes! Below are two printouts (one for 1RM testing and one for 5RM testing) that you can use with your athletes to help make finding Strength Numbers as easy as possible. Right-click the image to open in a new tab, then save and print to use.

7. How much weight should athletes add to the bar between sets?

There is no right answer to this question because it depends entirely on the athlete. A good rule of thumb to use with novice lifters is to always start with an empty bar, then add 5 to 10 lb each set until it starts to feel challenging. It also depends on the lift being tested: athletes will be usually be able to squat much more than they can clean or bench, so adding 20 lb to the bar will make more of an impact during a hang clean or bench press.

Also, performing lots of warm-up sets with lighter weight will not necessarily harm your heavy attempts—and once athletes have tested their numbers, they will have a better idea of what a good starting weight for their working sets should be. After athletes are experienced with testing, they should aim for 2-3 warm-up sets before beginning their working sets.

8. Can i use other movements (besides the clean, squat, and bench) to find my strength numbers?

As of now, no. If you want prescriptive loading in your Volt training program, you will need to test these 3 base lifts. We chose these specific movements for many reasons, including: their importance in sport performance training; their ability to be performed safely among a wide range of athletes; and their capacity to inform other movements based on category.

However, some athletes may be unable to safely execute these movements due to injury or other circumstances. While we do not recommend this, a coach can input "estimated" strength numbers for any of the 3 base lifts.

NOTE: Volt programs are designed for athletes WITHOUT injuries. Athletes recovering from injury should ALWAYS consult with a physician before being cleared starting an exercise program.

9. How often does volt prompt athletes to retest their strength numbers?

Volt will prompt athletes to retest their Strength Numbers during Challenge Sets in the final weeks of most Strength Capacity, Strength, and Max Strength blocks during the Preparatory phase. (Athletes will not be prompted to test during the Competitive or Transitional phases, as demanding training is not appropriate during those times.) Depending on the length of your training calendar, your athletes will typically retest every 3-6 weeks.

This also depends on your sport: endurance athletes, for example, do not require high levels of maximal strength, and thus will not see Challenge Sets very often.

10. I've entered my strength numbers, but i still see blank loading for some movements.

While most dumbbell and barbell movements will have recommended loading, some movements (like cable-based exercises) will always have blanks where loading should be.

This is because some machines are different from weight room to weight room. Because we cannot control for equipment consistency, Volt leaves these movements intentionally blank.

If your athletes have Strength Numbers, their program will ALWAYS prescribe weights for the most important movements (the ones that provide the greatest transfer to sport performance adaptations). When they do come across a blank movement, have them choose a resistance level that feels challenging for the prescribed number of reps.

Got a question we've missed? shoot us an email at and we will do our best to answer it fully!

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