This week, Tyrone Bell explains strength curves:
“In today’s video, we’re looking at how to really optimize tension to build more muscle in a faster time period. The way we’re going to achieve this is with the intelligent use of exercise strength curves. We’ll look at what exercise strength curves are, why we need to consider them and how to carefully incorporate them into your programs.
Before we get into this, I first need to make sure that we’re all on the same page with something that works hand in hand with strength curves – mechanical tension. Mechanical tension is basically the tension you place on your muscles with external load. High mechanical tension is considered the primary stimulus for muscle growth. The more tension you create within a muscle, the more size you’ll build.
What are Strength Curves?
All the exercises you perform in your training program have what’s called a strength curve. A strength curve is basically a graphical representation of the muscular force generated at each point throughout the range of motion. Because of joint angles, the resistance, or tension, of an exercise isn’t constant. The best way to explain this is with examples.
Let’s use easy-bar curls. Easy-bar curls have a strength curve known as a bell curve. When you perform the curl, the lift during the initial concentric phase starts easy. It increasingly gets harder until you hit the midpoint of the range of movement where your forearm is horizontal and the weight is furthest from your body. As you continue the movement and the weight moves closer to your body, the lift gets slightly easier again.
Now, let’s talk about the linear ascending curve. The difficulty will be highest at the beginning of the movement and the weight gets easier as you get closer to the completion of the range of movement. The barbell squat is a good example. It is hardest at the start of the concentric phase at the bottom of the movement.
The linear descending strength curve is the last of the most common strength curves. This is where the weight gets harder to lift as you get closer to the completion of the range of motion. Dumbbell lateral raises are a good example of this. The difficulty is the highest at the top of the concentric movement.
Why Are Strength Curves Important?
As mentioned earlier, mechanical tension is a primary key to triggering muscle growth. Looking at the strength curve of the easy-bar curl, we can pinpoint the range where the most mechanical tension is. For this example, it’s at the midpoint of the biceps contraction. This is where the most stimulus for a hypertrophy reaction will be. When you perform this exercise to absolute failure, your point of failure will be reached at the midpoint of the range of movement. The biceps fibers responsible for the midpoint contraction are the ones reaching absolute failure, which means you’ll fail there first, before the other biceps regions responsible for the top and bottom contraction range ever will.
Some may argue that you don’t need to account for different tension points of a movement. Just lift! But the concept of intra muscle, regional hypertrophy has been supported on the research front. A 2000 study tested regions within the same muscle and found that there is selective recruitment of different regions of a single muscle that are altered depending on the type of exercise performed. The most activated areas during the exercise would experience the most muscle growth due to undergoing the most amount of mechanical tension.
With that in mind, the big mechanism that can directly influence regional hypertrophy is the structured consideration of individual strength curves of the exercises in the program that you’re following. Identifying them, understanding them and knowing at what point of the range the most amount of mechanical tension is induced gives you a huge advantage. Then you can perform multiple exercises that complement and stimulant hypertrophy at all points of the range.
How to Incorporate Strength Curves
When you’re performing easy-bar curls, we already know that the greatest mechanical tension is at the midpoint of the lift. Let’s say we then perform spider curls, where the greatest contraction point is at the top, and preacher curls, where the greatest tension is at the start of the lift. Structuring these three exercises with complementary strength curves, you can create high muscular tension at all points of the targeted biceps’ range. This means we’re stimulating and triggering complete hypertrophy at the biceps.
Here’s another example to make sure it’s clear – your back. Starting with close-grip lat pulldowns, we place the greatest mechanical tension at the midpoint of the range. Next, do straight-arm pulldowns, where you make sure you get a tight squeeze and contraction at the end of each rep. Last but not least, dumbbell pullovers, which place the greatest mechanical tension at the start of the lift. This combination achieves high muscular tension at all points of the targeted back muscle.
When designing an exercise program there are a lot of factors that need to be considered and structured correctly for optimal response. Accounting for exercises’ individual strength curves and varying points of mechanical tension is a huge factor that I personally follow and work into my online client programs.
As a final take-home point, go through your current exercise program and find out the strength curves of everything you’re performing. Are they even accounted for? Are they providing your targeted muscles with high muscular tension at each point of the range of motion?
Granted, I’m not saying that all the points of each muscle have to go through high mechanical tension every session. You may perform a biceps session where the majority of the tension is placed at the midpoint. But if your program isn’t accounting for and stimulating the other points of the targeted muscle’s range using ascending and descending strength curve exercises, then you are seriously limiting your full development potential.”
All readers are advised to consult their physician before beginning any exercise and nutrition program. BPI Sports and the contributors do not accept any responsibility for injury sustained as a result of following the advice or suggestions contained within the content.

Build muscle Dumbbell pullovers Easy bar curl Hypertrophy Lat pulldowns Mechanical tension Muscle growth Muscle intelligence Muscle tension Preacher curl Spider curl Straight arm pulldowns Strength curve Tyrone bell