The reason this variation of the kettlebell curl is so great is due to the stretch the biceps (all elbow flexors) get from the angle the extended arm is in with the weight still providing some mechanical tension. It may sound obscure but micro-trauma and muscle damage are good as it results in significant levels of muscular hypertrophy. Reference pubmed.ncbi.nlm.nih.gov/24150552/ Combine this variation with peak contraction and you have an extremely awesome curl variation for hypertrophy.
“The primary benefit of executing peak contractions on a given repetition is that you’re able to intensify the contraction and therefore the stress on that particular muscle. The more stress you place on the muscle, the more muscle growth you stimulate.” Arnold Schwarzenegger
Let me also come straight out and tell you that a kettlebell is actually a really great tool for curling, actually much better than the barbell or dumbbell. The kettlebells design provides a mechanical advantage when it comes to curling, that advantage is high mechanical tension. In laymen’s terms, when you get to the end of the upper part of the rep with a dumbbell, that weight is resting right above your forearm, which means the tension on the elbow flexors is no longer there. However, when you use a kettlebell, even at the top of that rep the tension remains. The kettlebell still wants to fall away from the body and the elbow flexors (biceps curl) need to prevent them from falling.
If you’re interested in learning all the kettlebell curl variations then you should buy the book. To name a few:
- Squat Dead Curl
- Seated Curl
- Kneeling Curl
- Crush Grip Curl
- Hammer Curl
- Open Palm Curl
- Towel Grip Curl
- Flexed Static Hold
- Reverse Grip Curl
- Gorilla Curl
- Standing Curl (front)
- Standing Curl (side)
- Standing Curl (lateral)
- Standing Horn Grip Curl
- Bent-over Curl To Shoulder
- Bent-over Double-arm Curl To Chest
- And more…
The following is a quick breakdown of how to perform the kettlebell standing side curl.
- One leg straight
- One leg bent
- Push the hips into the straight leg
- Pull the elbow into the midsection
- Create a solid base to curl from
- Curl with a controlled speed
- End at the top
- Perform the negative part of the curl
The stance is important, and it requires some hip flexibility. Read much more about kettlebell curling in the book.