Your arms aren’t growing because of how you’re training them, not because of genetics. 1️⃣ Too much momentum If the weight is swinging, your biceps aren’t doing the work. Momentum takes tension off the muscle — and tension is what builds size. 2️⃣ No control on the negative The lowering phase is where most growth happens. If you’re dropping the weight, you’re skipping half the stimulus. 3️⃣ Ego weight over tension Lifting heavier than you can control looks strong, but it limits range of motion a