Have you ever noticed that lifting the same weight feels different at various gyms—or even on different machines in the same gym? You didn't lose or gain strength overnight - this is possible, and intentional.
While the weight on the stack doesn’t change, the force you experience can vary. This difference comes from the machine’s cable ratios and pulleys, which are used to create either a mechanical advantage (making the weight feel lighter) or disadvantage (making it feel heavier).
Keep reading to see why this is necessary, which machines to use, and how to determine how much you are lifting.
Why Does the Weight Feel Different?
When you move from one gym to another, or even from one machine to the next, the weight on the stack might remain the same, but the effort required to lift it can change. This is because gym machines use varying cable ratios and pulleys, which affect the amount of weight you feel at the handle.
It’s important to note that the weight doesn’t actually change—40kg on the weight stack is still 40kg. However, the machine's setup alters how much force you must apply to move that weight, which is why it can feel heavier or lighter.
Mechanical Advantage vs. Disadvantage
At the core of these differences is a concept known as mechanical advantage. When a machine is designed to create a mechanical advantage, it reduces the force needed to move the weight, making it easier for you to lift. On the other hand, machines with less mechanical advantage require more force to lift the same weight, making it feel heavier.
Machines that use pulleys to create mechanical advantages do so by distributing the load more efficiently. This makes the movement smoother and easier, but it also means you aren’t lifting as much actual weight as the stack might suggest.
Understanding Cable Ratios
Cable ratios describe the relationship between the weight selected on the stack and the resistance you feel at the handle. Common ratios include 1:1, and 2:1, and less common are 3:1, and 4:1, and they can have a significant impact on how the weight feels during your workout.
1:1 Ratio
In a 1:1 system, the resistance you feel is (almost) equal to the weight on the stack. So, if you select 40kg, you’ll feel 40kg of resistance at the handle. Machines with a 1:1 ratio tend to offer the most direct experience, where the weight moves in sync with the cable, and for every 1m you move the handle, the weigt moves 1m, making them ideal for exercises that target large muscle groups like lat pulldowns or rows. This ratio provides no mechanical advantage, so you're lifting the full weight.
2:1 Ratio
In a 2:1 system, the resistance you feel is halved. If you select 40kg on the stack, you’ll feel 20kg of resistance. This type of machine gives you a mechanical advantage, making the weight easier to lift while allowing for smoother and more controlled movements. The distance the weight moves is halved, if move the handle 1m, the weight moves .5m. It's commonly found in machines designed for smaller muscles or rehabilitation work, where precision and control are key.
3:1 and 4:1 Ratio
These are less common. However, like the other ratios the weight felt at the handle will feel different, and the weight will move even less. 3:1 will be a third of the weight, 4:1 will be a quarter of the weight.
In addition to changing the force you feel, these ratios also affect how far the cable moves compared to the weight stack. In a 1:1 system, the cable moves the same distance as the weight stack. In a 2:1 system, the cable moves twice as far, and in a 4:1 system, it moves four times as far.
While machines with higher ratios offer smoother motion, you’ll be lifting less total weight.
The Role of Pulleys
Pulleys play a key role in how much force is needed to move a weight on cable machines. The more pulleys added, the less force you need to exert to move the same weight. For example, a dual pulley system often has a 2:1 ratio, meaning if you set the weight stack to 40kg, you'll only feel 20kg of resistance at the handle. This is because the extra pulleys distribute the load, making the weight feel lighter.
However, pulleys also introduce friction, which slightly alters the feel of the weight, but they’re primarily there to reduce the force needed to lift. For example, if a machine has multiple pulleys and a 4:1 ratio, the 40kg weight on the stack will feel like 10kg at the handle, allowing you to perform faster or more controlled movements without straining.
Single pulleys are often a 1:1 ratio, while dual pulleys are often a 2:1 ratio.
Below is a diagram showing a 1:1, 2:1, and 3:1 cable machine pulley system.
Why Different Ratios
In most gyms, you’ll notice that different machines are designed with varying ratios, or number of cables, depending on the exercise they’re intended for.
1:1
These machines are typically found on larger, more robust equipment like seated row machines, lat pulldown stations, and leg press machines. The higher weight resistance and larger increments make them ideal for exercises that target big muscle groups, such as your back and legs. Since the weight feels heavier with a 1:1 ratio, they’re better for building strength and progressing with heavier loads.
2:1
You’re likely to find these machines on the inner sections of large cable crossover stations or dual adjustable pulley machines. These setups are perfect for exercises that focus on smaller muscles, such as pec flyes, triceps pushdowns or bicep curls, where the movements require more control, and the smoother glide of the 2:1 ratio makes it easier to focus on form. They’re also great for rehabilitation exercises, where lighter resistance is needed.
3:1 and 4:1
These are less common but can be found in functional training areas or on machines designed for fast or dynamic movements, such as jump squats or rotational core exercises. The 4:1 ratio allows for greater range of motion and faster cable movements while keeping the resistance low, making it ideal for exercises that require speed or precision over brute strength.
Equation to Calculate Effective Weight
It is still possible to move from gym to gym, or machine to machine, while knowing how much you are lifting.
Effective Weight = Weight Selected / Cable Ratio
For example, if you are lifting 20kg on a dual pulley system (2:1 ratio), the calculation would be:
Effective Weight = 20kg / 2 = 10kg
Summary of Cable Ratios
1:1 Ratio: Effective Weight = Weight Selected (e.g., 20kg = 20kg)
2:1 Ratio (Dual Pulley): Effective Weight = Weight Selected / 2 (e.g., 20kg = 10kg)
3:1 Ratio: Effective Weight = Weight Selected / 3 (e.g., 20kg = 6.67kg)
4:1 Ratio: Effective Weight = Weight Selected / 4 (e.g., 20kg = 5kg)
This formula allows you to determine the actual resistance you are lifting based on the selected weight and the machine's cable ratio.
The weight you feel on a machine can vary widely depending on its cable ratio, pulley system, and purpose.
While the weight on the stack stays the same, the force you feel changes based on how the machine is designed. Understanding how these ratios work can help you choose the right equipment for your goals—whether you're aiming to build strength with a 1:1 machine or improve control and precision with a 2:1 setup.
The next time you step into a gym and notice a weight feels different, remember you can determine the ratio by checking the machine, or if you are still uncertain, ask the staff which ratio that machine is.
I hope this helps, happy cable machine lifting!
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