Weight Training Calculator

You keep lifting and you’re still not gaining that extra strength and muscle? Operate in the right rep range, and you will!

After you find your rep max for any exercise, continue on to learn more about the different rep ranges below the calculator and reach your goals faster.

Why is Having a Weight Training Calculator Important?

This handy weight training calculator uses Brzycki’s one rep max formula to calculate your one-rep max, then based on percentages shows you multiple rep max quantities for any exercise.

Results above your 12 rep max have a higher rate of inaccuracy, so that’s as high as this calculator goes.

It’s extremely helpful to know your various rep max quantities before you plan on following any sort of rep scheme. Most people follow this rule of thumb when it comes to rep schemes:

  • 1-6 reps: Strength
  • 5-8 reps: Strength/Hypertrophy
  • 8-12 reps: Hypertrophy
  • 12-15 reps: Endurance

To get the most accurate results, use enough weight during an exercise to reach muscle fatigue within 4-6 repetitions, and then enter your information into the calculator below.

Keep in mind that these are estimates, and although they are beneficial to have on hand during your workout, you should listen to your body above all else and always avoid exercising a muscle beyond fatigue during any set you perform.

How to Build Muscle and Increase Strength Through Various Rep Ranges

there is more to building muscle and increasing strength, however than merely following a rep scheme. Other factors indeed come into play. Here are some of them:

Weight on the bar

Resistance plays a role in gaining strength. The more weight on the bar that you can move, the stronger you are. If you want to build muscle, you need to use a lot of resistance for multiple reps.

Increasing the weight over time will translate into muscle gains as a result of an increase in strength.

Volume is king

Low reps with more weight on the bar were believed to be sub-optimal for muscle growth. However, studies show that this is false. Overall training volume is the key determinant.

For example, you can perform one rep of 100 lbs or split that into two reps of lbs kgs. Total reps x load = volume.

As long as you increase the volume over time, and your rep rage doesn’t go higher than 15, strength and muscle gains will follow.

Neural drive

Lifting heavy weights is a skill. It involves a lot of technique, learning proper angles, and also experimenting with your anthropometry to optimize performance.

For many people, the road to lifting heavy weights did not just happen overnight.

It took weeks, months, and years of practice to not only become efficient at performing the compound lifts but also adding weight to the bar while minimizing injury.

Repeatedly practicing a lift is a way to increase neural drive. In doing so, you train the muscle more effectively.

Muscle fiber types

There are no two people with the same muscle fiber types. Those same two people could be on the same training program but see different results.

All other factors constant, however people are made differently; hence, the results of a training program may not necessarily be the same across the board.

That said, it is still expected that an increase in strength will eventually lead to an increase in muscle. The rate of growth, however, will vary slightly from person to person.

Fascicle length/volume

The fascicle length is the most common way of measuring the length of a muscle fiber. Fascicles are bundles of muscle fibers.

An increase in the length of a fascicle generally reflects an increase in the volume of a fascicle. When there’s an increase in length, there’s also an increase in the number of contractile units.

More units mean more strength gains especially at peak contractions with longer muscle lengths.

You must increase training volume slowly over time, which you can do through periodized training. Your program can cover systematic variations in training volume, training intensity, and exercise specificity.

Different training models are utilized to accomplish this, namely linear, undulating, and conjugate sequence. Mesocycles and microcycles are manipulated in such a way that individual phases in your training program are suited for a specific goal.

Common Training Protocols

Using, block periodization, you plan three longer cycles, which each focus on a particular goal. The first cycle makes you focus on hypertrophy and muscular conditioning.

During this period, you perform specific exercises in sets of 12 – 15 repetitions. In this rep range, mechanical tension and metabolic stress are accumulated which is essential for hypertrophy.

The second mesocycle makes you focus more on strength. During this mesocycle, you perform repetitions in the 8-12 rep range.

The third mesocycle makes you focus on power and puts significant stress on your nervous system that encourages muscle adaptation. During the strength mesocycle, you perform repetitions in the 1-8 rep range.

High Reps or Low Reps: Which is Better?

It’s not uncommon to see trainees switch to high reps during a fat loss diet to bring out more detail in the muscle.

However, keep in mind that muscle definition is the result of a combination of muscle development and low body fat percentage, not a particular rep scheme.

Low reps, on the other hand, are favored during a bulk because it is said to be better for building mass through an increase in strength.

Commonly strength programs tend to accumulate training volume earlier in the training cycle in the 6-12 rep range before it tapers off towards the end of the cycle or the ‘peak’ with the 1-3 rep range.

The Size to Strength Disparity

In tackling the disparity between size and strength, it’s important to look at myofibrillar hypertrophy and sarcoplasmic hypertrophy.

Myofibrillar hypertrophy occurs when there is an increase in myosin/actin filaments in the cell. This leads to strength gains and an increase in the size of the contractile unit of the muscle.

Together, this means an increase in force production, which is commonly referred to as functional muscle.

Sarcoplasmic hypertrophy occurs when there’s an increase in myosin-acting filaments. The filament area decreases while the cross-sectional area of the muscle increases, without an increase in strength.

Size without much increase in strength is more common in bodybuilding as it involves the growth of the sarcoplasm without directly contributing to force production.

The Final Word

Is there a relationship between muscle growth and strength? Yes, definitely.

When we work on muscle growth, we increase our strength and vice versa. Typically, increasing your physical strength requires heavy training which produces any or all of the following effects:

  • Increase in muscle mass
  • Increase in lateral force transmission
  • Increase in tendon stiffness
  • Increase in voluntary muscle activation
  • Improved coordination (load-specific)

But if you were to reduce the load on the bar to do more reps (such as during a hypertrophy or bodybuilding program), smaller improvements in coordination, tendon stiffness, voluntary muscle activation and lateral force transmission may be observed.

Powerlifting or strength programs use heavier loads with fewer reps, and are likely to achieve better gains through 1-5RMs, and may only show a moderate relationship between muscle growth and strength.

On the other hand, bodybuilding or hypertrophy programs may achieve gains in strength as a result of increasing muscle size and will see a link between muscle gains and strength increases.

Now, what questions do you have about weight lifting?