How Do You Know If You're Lifting The Right Amount Of Weight?

Mar 23, 2025

When it comes to getting stronger and putting on muscle, it’s not always about how heavy you lift - it’s about how effectively you challenge your muscles. You don’t need to chase the biggest dumbbells in the gym to see results, but you do need to challenge yourself enough to stimulate change.

So, how do you know if you’re lifting the right amount of weight? Let’s break it down!

🪶 Signs You’re Lifting Too Light

If your goal is to get stronger, lifting weights that are too light unfortunately won’t cut it. Here’s how to know if you need to go heavier:

You can do 30+ reps easily. If your goal is to build strength and muscle, then you'll want to keep your reps 30 and under. If you’re breezing through with perfect form and still feel "fresh", it’s time to increase the weight!
You’re not feeling challenged by the last few reps. The last 3-4 reps should feel noticeably harder and your movement should slow slightly as you approach fatigue. If you’re still powering through with ease, grab a heavier pair of dumbbells, baby 😎
No post-workout muscle fatigue. Soreness isn’t a sign of "success," but if you consistently finish workouts feeling like you could easily repeat them, you’re probably lifting too light. Your muscles should feel tired or worked, even if you’re not sore the next day.
You’ve hit a plateau. If you’ve been doing the same routine with the same weights for weeks or months and are no longer seeing progress in strength, endurance, or muscle tone, it’s a sign you need to increase the intensity. Let's go!

🛑 Signs You’re Lifting Too Heavy

On the flip side, lifting weights that are too heavy can compromise your form and feel really uncomfortable! Watch for these red flags:

Your form breaks down quickly. If you’re struggling to maintain good posture or joint alignment, the weight is too much. Form always comes first.
You can’t complete your set range. For example, if you’re aiming for 10-12 reps but only manage 4-5 before losing control, it’s too heavy.
You rely on momentum. Swinging your body or using jerky movements to lift means the weight is too challenging. You want controlled, smooth movements.
It feels terrible on your body. Enough said 😜

🎯 How to Know You’ve Picked the Right Weight

You’ll know you’ve hit the "sweet spot" when:

The last few reps feel tough but doable. During the final 3 or 4 reps, you should notice your movement starts to slow slightly (your heart rate might spike as well) - this is a good sign you’re nearing muscle fatigue. Your muscles should feel pretty tired by this point.
You maintain proper form throughout. Even when it gets hard, you’re able to keep good technique without compensating.
You feel challenged but not defeated. You should finish your set feeling like you gave a solid effort, but you could still complete another round after resting.

🏋️‍♀️ How to Safely Choose the Right Weight

Start with a light to moderate weight if you’re unsure—it’s always better to begin lighter and assess from there. Aim for a weight that allows you to complete 10-15 reps with good form.
1. In MOVEHAPPY classes, we work for 45-60 seconds per set rather than counting reps, which typically equals 30 reps or less.
Increase the weight when you can comfortably finish all reps without much effort.
Test for muscle fatigue: If your last 3-4 reps feel slow and challenging but controlled, you’re in the right range.
Prioritize form over weight. A perfectly executed set with moderate weight is far more effective than sloppy reps with heavy dumbbells.

💡 The Bottom Line

Getting stronger isn't about maxing out on weight - it’s about progressively challenging your muscles with good form over time. Pay attention to your rep range, how your muscles feel during those final reps and don’t be afraid to adjust your weights regularly. Progress happens when you find that sweet spot of challenge and control.