If you’re new to strength training, you might find yourself asking, what are dumbbells measured in? It’s a common question, and understanding the answer is key to choosing the right weights for your goals. The units used can vary depending on where you live and what type of dumbbell you’re looking at.
This guide will break down everything you need to know about weight measurement for dumbbells. We’ll cover the standard units, how to convert between them, and what to look for when your buying equipment.
What Are Dumbbells Measured In
At its core, dumbbells are measured in units of mass. The two primary systems you’ll encounter are the Imperial System and the Metric System. The unit displayed on a dumbbell tells you it’s heaviness, which directly relates to the force you need to lift it against gravity.
Knowing this helps you track progress accurately and follow workout plans correctly. Let’s look at each system.
The Imperial System: Pounds and Kilograms
In the United States and a few other countries, the imperial system is standard. Here, dumbbells are labeled in pounds (lb). You’ll see dumbbells marked as 5 lb, 10 lb, 20 lb, and so on.
This system is straightforward if your used to it. A 10-pound dumbbell has a mass equivelent to 10 pounds. Most home gym sets and adjustable dumbbell kits in the U.S. use pounds.
The Metric System: Kilograms
The majority of the world uses the metric system. Here, dumbbells are measured in kilograms (kg). You’ll find dumbbells marked as 2 kg, 5 kg, 10 kg, etc.
Kilograms are part of the International System of Units (SI), making them the global standard for science and most sports. If you see a dumbbell with a number followed by “kg,” you know it’s measured in kilograms.
How to Convert Between Pounds and Kilograms
Since programs and equipment can use either unit, knowing how to convert is essential. The conversion is simple:
* To convert pounds to kilograms: Divide the number of pounds by 2.205.
* Example: 10 lb ÷ 2.205 ≈ 4.54 kg
* To convert kilograms to pounds: Multiply the number of kilograms by 2.205.
* Example: 5 kg × 2.205 ≈ 11.03 lb
For quick mental estimates, you can remember that 1 kg is roughly 2.2 lb. So a 10 kg dumbbell is about 22 lb.
Understanding Dumbbell Weight vs. Plate Weight
This is a crucial distinction, especially with adjustable dumbbells. The weight marked on a fixed dumbbell refers to the total weight of the entire object you pick up.
For adjustable dumbbells, the weight is usually the sum of the plates you add to the bar. But you must also account for the weight of the bar and collars. A typical adjustable dumbbell handle might weigh 2-3 kg (5-7 lb) by itself.
Always check if the listed weight includes the handle or just the plates. This prevents surprises during your workout.
Reading Dumbbell Markings Correctly
Dumbbells usually have their weight stamped or engraved on them. Look for:
* The number (e.g., 10)
* The unit (e.g., lb or kg)
* Sometimes, the weight is shown in both units (e.g., 10 lb / 4.5 kg)
If a dumbbell feels lighter or heavier than expected, double-check the marking. Wear and tear can sometimes make them hard to read.
Choosing the Right Weight For Your Goals
Knowing the units is one thing; applying them is another. The right weight depends on your fitness objective.
For Muscle Building (Hypertrophy):
You typically want a weight that allows you to perform 8 to 12 repetitions with good form before reaching muscle fatigue. If you can do more than 12 easily, the weight is to light.
For Strength and Power:
Focus on heavier weights that allow for 1 to 6 reps. This requires a weight that is challenging while maintaining perfect technique to avoid injury.
For Muscular Endurance:
Lighter weights are used for higher repetitions, usually 15 to 20 reps or more. The weight should be manageable but still cause fatigue by the end of the set.
A simple process to find your starting weight:
1. Pick an exercise, like a bicep curl.
2. Select a dumbbell you think you can lift 10 times.
3. Perform the exercise with good form.
4. If you could do more than 12 reps easily, try the next heaviest weight next session.
5. If you struggled before 8 reps, try a lighter weight.
Special Cases and Other Measurements
Not all dumbbells use simple pounds or kilograms. Here are some other things you might see.
Rubber-Coated and Urethane Dumbbells:
These often list weight in kilograms, even in the U.S., as they follow international manufacturing standards. Always check the small print.
“Olympic” Dumbbell Handles:
These are less common but use the same standard as Olympic barbells. The plates are measured in kilograms, and the large hole is 2 inches. The handle itself can be quite heavy.
Ancient and Vintage Dumbbells:
You might come across old dumbbells measured in non-standard units like stones (1 stone = 14 lb). This is rare today but interesting from a historical perspective.
Common Mistakes and How to Avoid Them
* Assuming All Dumbbells Use Your Local System: Always look for the unit symbol (lb/kg).
Ignoring the Handle Weight: With adjustable sets, add the weight of all plates plus the handle to get the total.
* Confusing Weight for Difficulty: A 10 lb dumbbell might be light for a squat but heavy for a lateral raise. Exercise choice matters.
* Not Considering Material: A 10 kg iron dumbbell and a 10 kg rubber dumbbell are the same weight, but the size and feel can differ, which might affect your grip.
Taking a moment to verify the mesurement can save you from a unproductive or unsafe workout.
FAQ: Your Dumbbell Measurement Questions Answered
Q: Are gym dumbbells in kg or lb?
A: It depends on your location. Gyms in the U.S. and Canada typically use pounds (lb). Gyms in Europe, Australia, and most other places use kilograms (kg). When in doubt, ask a staff member.
Q: How do I know if my dumbbell is lbs or kgs without a marking?
A: You can use a bathroom scale. Weigh yourself alone, then weigh yourself holding the dumbbell. Subtract your weight—the difference is the dumbbell’s weight. Compare the number to a common conversion; a number like 4.5 or 9 is likely kg, while 10 or 20 is likely lb.
Q: What does ‘kg’ mean on a dumbbell?
A: ‘kg’ stands for kilogram, the metric unit of mass. A 5 kg dumbbell has a mass of 5 kilograms.
Q: Why are some adjustable dumbbell weights misleading?
A: Sometimes only the plate weight is advertised. A kit advertised as “40 lb set” might include 40 lbs of plates, but the two handles could add another 10 lbs, giving you a total of 50 lbs of equipment. Always read product descriptions carefully.
Q: Is it better to train in kg or lb?
A: There is no physiological difference. The better system is the one you understand best and can consistently track. If you follow a workout program, use the units it specifies to ensure your following the intended load.
Understanding what dumbbells are measured in empowers you to train smarter. You can accurately track your progress, follow any workout plan, and make informed purchases. Remember to always prioritize good form over lifting heavier weight, and use the units as a tool to guide your fitness journey. Now you have the knowledge to pick up the right weight—literally—for your needs.