The concept of the golf swing transition has seen a lot of discussion on the Rotary Swing Forums as golfers try to understand what it is and how you time it, what the bump is, and how it all fits together.
We're going to take a few minutes today to discuss exactly what the bump is by reviewing a student's swing from the Members Vault.
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This student posted his swing to the 21+ handicap group, so you'll see a few setup flaws that are causing him some trouble, but for now we're mainly concerned with his transition move — or lack thereof — and how the hips work in the golf swing.
Student at setup (left), and at the top of the backswing (right)
We've drawn a red line on the outside of this golfer's lead thigh, to serve as a fixed reference point throughout the swing.
What you'll notice is that he takes the club back without ever moving off that line. He stays very centered, takes the club back primarily with his arms and shoulders, and doesn't really use his lower body in the backswing at all.
Wait. The Lower Body?
A lot of golfers will hear that and ask what we mean by "using the lower body to take the club back."
There's a lot of misunderstanding and misinformation out there about not rotating your hips going back. A lot of people take that advice and overdo it.
Your lower body absolutely does rotate during the backswing.
There was a point in golf, with whiffier shafts and the like, when you didn't want to put a tremendous amount of stress and load on the shaft, and as a result golfers tended to get a lot of hip rotation in the backswing and through.
These days we have a much better understanding of the mechanics of the swing and how the equipment works, but that doesn't mean that in trying to create X-factor or torque that you don't turn your hips at all. In fact, the opposite is true. You must have hip rotation going back.
Tiger Woods at setup (left), and at the top of the backswing (right)
We'll take elite players as an example. Although from the face on view it looks like they don't really turn their hips a whole lot, if you look at it from down the line you'll see that the lead knee works quite a ways out over the lead toe. It's harder to see in this view, but you can still tell there's some rotation going back.
Elite players are really loading up and using their legs and hips to rotate and bring the club back. Think of somebody like Roger Federer or Nadal, loading up for a serve. They really use their legs to load up and get a lot of power in the golf swing, and it's no different.
It's hard to articulate exactly what golfers see or don't see in their swings, but you can see here that as elite players start to load up they get a lot of torque and load in the lower body. If you want to evaluate your own transition, the AI swing analyzer can measure exactly how well you're shifting into your lead side.
Here's What Happens When You Don't
We see elite players making a very athletic move that allows them to use their lower body to load up going back and really unwind it coming down.
The student's downswing
By contrast, our student's swing doesn't show that liveliness or activation in the lower body. It's more like he just turns into his trail thigh a little bit.
He's not really loading or getting ready to go back the other way. He turns a little, but he doesn't build up any power or torque in the swing. He barely ever gets past the red line we drew at address.
He starts the downswing with his arms, hands, and club, bringing everything down. His hips are moving at about the same speed as his shoulders, so he's not getting any lower body power out of the downswing at all.
By the time he gets to impact, he's broken down a little bit. There are a number of other things we could talk about in the swing, but for now notice that his lead leg is almost back to where it was at address. In other words, he missed the bump.
So What is the Bump?
The bump is the transition move at the top of the downswing to really set into the lead side and fire your body through, bringing the club down with your legs. That's what's missing in our student's swing. The GOAT Drill system is specifically designed to train this exact loading and transition pattern into muscle memory.
The student's impact position
He missed it because he didn't wind up on the way back. He just kind of lackadaisically turned back; he got the club back, but he didn't use his big muscle groups.
Now as he unwinds of course he's forced to flip the club coming down, as we can see from his impact position.
Let's take a look at that same segment of the swing from elite players.
The lead hip gets past that line immediately, right from the top of the downswing. That's the bump.
It's the aggressive setting into the lead side, and it means that by the time they get into impact position the center of the body or the belt buckle is out on that hip line.
Our student, meanwhile, is much farther back behind the line. That's part of the reason he's flipping and doesn't have any shaft lean at impact — his body is too far behind at impact.
Tiger's "bump" move, setting into the left side at the top
Most importantly, elite players get forward into that position very early. By the time the hands are in front of the trail leg, the center of mass is already set onto that line, while our student never has a chance to get there. He's just trying to continue to turn through.
Watch the Foot Line
There does have to be some lateral movement in the golf swing, and our student is not really getting any. One way we can tell this is because his trail foot starts to spin out and actually work back behind him.
- Check this in your own swing:
Simply draw a line on the outside of your trail foot. If your heel ever breaks that plane line, you'll know you're spinning out as you go back.
Tiger's heel never breaks the right foot line
If your trail foot works backwards it means you're not getting enough lateral transition onto your lead side to allow your legs to bring the club down.
Checking the same thing in the elite model swing, we see of course that the foot never breaks that line.
The trail heel comes straight up on the line as they set aggressively into the lead side and continue to turn and drive through. This shows that they got a good transition early in the downswing to allow the hips to continue to rotate and drive through.
The line drawn on the lead hip at address now runs down the center of the body, hip, and leg. They're delicately balanced on the tip of the trail toe, showing that there's no longer any weight on the trail side at all.
Our student, meanwhile, never got fully onto his lead side. His trail shoe is bent, showing that he's still bearing weight on his trail foot at the end of the swing because he missed the transition and never got off the trail side.
The student's heel breaks the right foot line in the follow through
This is very common among higher handicap golfers; they don't get loaded up going back, so they can't drive and fire through on the way down. They tend to over-power it with their upper body, while the whole lower part of the body is taken out of the equation.
That's why, when you compare that to the elite swing model, the lower body doesn't look very powerful at all in the student's motion. Elite players use their body to make sure they really get off that trail side onto the lead, which you can see clearly in the reference swing.
Right from the beginning, you'll notice that the best players are loading up, really getting some load and spring into the legs, driving very hard, getting onto that lead side.
Is This Just a Slide?
By now a lot of people are thinking, "I thought there was no lateral motion. Isn't this a slide?"
A slide would be if they continued to move the hips out as the club approached impact, but the lateral movement stops long before impact.
As you can see in the final photo, the hips stop moving laterally before the hands even reach the trail thigh. If we draw another line there we can see that they never move past that line.
A slide would be if they continued moving the hips out past that point into impact, and ended up coming too far from the inside.
Tiger's hips stop moving laterally before impact (left)
This movement is the bump and the transition, and it does involve lateral movement in the downswing, as you can see from the lines we drew at address.
Your legs must drive that first part of the downswing in order to get everything to sync up for maximum power with minimum effort.
Hopefully this will clear up some of your questions about the transition and the bump we mentioned in the book.
If you're not getting fully onto your lead side, work on your transition, get that bump, and you'll have a lot more power and clubhead speed with a lot less effort in your swing.
Watch part 2 now to see how you're moving your body in the opposite direction of the pros!
