A question I am often presented with early on in most sessions is “what’s my sequence, is it good?” First of all, we need to define what good is and secondly we need to look at if can we change swing function by focusing on adjusting the sequencing or is sequencing the product of movement, function/dysfunction?
My own view and it is one of irony, is that biomechanics is often taught in the wrong sequence, where beliefs are that in order to improve swing function people head straight to the kinematic sequence to solve the problem, identify where there may be some imbalances, whether it be in peak speed order, segment transition order, timing lags between the segments, amount of stretch, rate of stretch/recoil, rate of acceleration/deceleration and rotational speed and then try and adjust these directly in an attempt to solve the problem. Now, let me just start by stating one point- sequencing is vital and a crucial influence on efficiency, consistency, power/speed production, maximising the force-velocity capabilities of muscle-tendon units, injury prevention and is often seen as a signature of skilled golfers (although I have worked with many successful players who present with less than optimal sequencing patterns-more on this in future articles). However, in the true fashion of cause and effect, I believe the approach needs to be as to not look at what is happening, but why is it happening?
Before we progress further, let’s clarify what the key terms mean when discussing kinematic sequencing as often mis-interpretation of them can present many problems.
Peak speed order – This refers to the point in back/downswing where the segment has reached its peak speed and then consequently, where in relation to the other segments in the chain this peak happened. An ideal peak speed order in the downswing would be pelvis, trunk, lead arm, hands and club head
Timing lag – this indicates the difference in time between when each segment reaches peak speed. This is vital as if the gap is too long, then often the energy produced by the segment is lost and absorbed in the body, alternatively if the gap is too small then this does not provide sufficient time for energy to get passed on to the next segment. Optimal is typically between 25-35ms
Transition order, the order the segments change direction in from back to downswing.
Rate of acceleration/deceleration, effectively how fast the segment accelerates and decelerates which is often linked to coordination, flexibility, control/stability, strength etc..
Amount of stretch, rate of stretch/recoil. In simple language, muscle/tendons unit act similar to elastic bands, the more they stretch, the faster they stretch and the quicker they recoil, the more force and speed is produced. Known as stretch shortening cycles, these cycles exist across many joints in the golf swing, such as trunk-pelvis, lead arm-trunk, wrist-elbow. Typically, longer hitters are the ones that maximise these principles and have higher levels of stretch-recoil. Although there is more to it than just this.
Rotational speed, simply put how fast each segment is rotating.
So lets look at an example of good sequencing:
If you look to the bottom corner of the screen, you should note how a numerical description is given for the order the segments reach peak speed in the downswing, in this case 1-2-3-4. This would be considered optimal.
Below is an example of less than ideal sequencing:
This provides one example of many dysfunctional sequences, in this instance you’ll note how the pelvis doesn’t start to decelerate greatly until after impact, and the trunk reaches peak speed after impact. In essence, a very inefficient way of transferring energy produced through the body into impact. This players sequence was classified as 1-3-2-4. Additionally, they exhibited slow peak pelvic speeds, poor timing lags and low levels of amount of stretch, rate of stretch and rate of recoil. However, this leads us back to the discussion as to approaching the problems presented by the golfer and attempting to address the issues displayed in the kinematic sequence as a means of solving the problem.
Case study – poor kinematic sequencing.
I believe that good biomechanics starts with good posture and effectively, one definition I would use to describe good swing function is how well the golfer sets static posture at address (although classed as static, there is still lots of subtle movement happening within the body which is called postural sway) and then how well they control their posture dynamically within the swing. Combine this with a well matched up hand, arm and body action then you are little closer to having good swing function. For the benefit of this article, we are going to ignore swing concepts as I would like to keep the focus purely on how sequencing is affected by movements happening in the swing, therefore effecting sequencing.The golfer presented themselves with a clear anterior tilt (excessive arch/lordosis) in their lumbar spine which lead to their pelvis having too much forward bend at set up. The challenge is, when the pelvis sits like this in simple terms the hip joints lock up due to the angle the femur (thigh bone) sits in the hip socket, effectively the hand brakes are on! This is a problem as there are three main areas where the golfer produces rotation from in the golf swing, firstly the thoracic spine and secondly both hip joints. However, the golfer’s neurological system (GPS) knows where the top of backswing is so it will find a way of moving around this problem in order to find the top of backswing. Digressing slightly, this can lead to many other problems such as stress through the SI joints, excessive lateral flexion through the spine and wrist/neck compensations discussed in previous articles.
Because of these postural imbalances at set up, this player found that in order to move around the problem and rotate, they compensated by allowing their pelvis to move excessively towards the target with the spine having large amounts of left side bend at the top. Therefore their recovery move was for the pelvis to back up away from the target, the ribcage to move further ahead of the ball (as shown below) through impact with disconnection happening between right arm and ribcage.
The blue curve on the graph above represents the lateral translation (side to side movement along the X axis) of the ribcage during the swing. You should note here how the blue curve goes up significantly from top of backswing to impact which is charting the movement of the ribcage towards the target, and then on impact it rapidly drops which is showing how the ribcage then backs up away from the target.
In the graph below, the blue curve represents the swaying motion of the pelvis. On observation, you’ll see how the curve moves up from address to the top which is showing how the pelvis sways towards the target. However, on impact and just after, you’ll see how the curve flattens. This is highlighting the pelvis essentially moving away from the target. In my role, I examine movements both globally and locally, therefore this could be considered a cross pattern (counter balance ) movement whereas the pelvis is backing up through impact as a consequence for how the ribcage has moved ahead of the ball in transition. Once more, this is a good example of how the brains GPS system will auto correct when it detects that segments aren’t where they need to be. When working well, It has to be the world’s best SatNaV!
So how does this relate to the kinematic sequence shown earlier?
Hopefully you can see that from the patterns the player had, the breakdown lying in how the pelvis sits at set up, the compensation being how they effectively rotated around this despite the adaptations that happened through the body as a result of the posture, then finally how they recovered in order to find impact. From a sequence perspective, it was simply a reaction to how they player was setting static posture and then how they attempted to control dynamic posture (posture in swing). Hence, the pelvis slowed down post impact and the ribcage reached peak speed after impact as it was backing up much quicker than it was when it was moving ahead of the ball in transition. So the question I present is this, where on the sequencing graph does it show this global pattern? Therefore, I believe that although sequencing is extremely valuable and offers some critical and very sensitive and influential data, understanding the movements that underpin good sequencing and investigating the issues that are shown from a cause and effect perspective will invariably then influence sequencing without actually having to consciously do.
Just for the record, after the player made the postural improvements (this was a combination of addressing the structural imbalances associated with a pattern described by Vladimir Janda as lower cross syndrome and using biofeedback to improve the awareness and feel of good pelvic posture), biofeedback was given to encourage the player to move their ribcage around their spine better whilst loading their right hip joint in the backswing, this then allowed the player to move more effectively in the downswing by matching up pelvis, trunk and arms up on impact. Consequently, here is the sequence after this process:
On conclusion, sequencing is a vital aspect and influence on ball striking, however for future reference when presented with a less than ideal sequence, don’t look at what has happened, lets figure why it happened because invariably to solve the problem, you have to work away from the problem!