For some. For those who are just getting started with fitness and wish to build muscle mass while establishing a fundamental level of strength, a 5 kg kettlebell is a great starting point. However, if you have ambitions of substantial muscle growth, you will soon find the 5 kg kettlebell insufficient. As your strength advances, consider gradually ramping up the weight to challenge your muscles and promote their growth.For some. For those who are just getting started with fitness and wish to build muscle mass while establishing a fundamental level of strength, a 5 kg kettlebell is a great starting point. However, if you have ambitions of substantial muscle growth, you will soon find the 5 kg kettlebell insufficient. As your strength advances, consider gradually ramping up the weight to challenge your muscles and promote their growth.