I've read lots of articles and watched lots of videos about throwing forehands (and thrown lots of forehands!), and I think there's still space for me to say something that hasn't been laid out as clearly as I hope to lay it out here.
Here's the theory: throwing a forehand without wobble mainly relies on two things:
First: the way you grip the disc.
Second: the way your wrist rotates.
There is more than one way to combine those two factors to create a throw that doesn't wobble. But, I believe that one of those combinations is better than others. Changing our grip can play a big role in reducing disc wobble, and I think this fact is underappreciated.
Wobble is when the disc doesn't rotate around its axis of symmetry
First, let's understand why a frisbee sometimes wobbles when thrown.
A frisbee (that isn't bent out of shape) is an object with rotational symmetry.
Take this 2D shape:
And rotate it 360 degrees around this axis:
And you've created a 3D frisbee.
When throwing the disc, if it rotates around this same axis, it spins with no wobble. Here's what that clean spin looks like, with thanks to this article by Benji Haywood for making the GIF which I'm shamelessly stealing:
If it rotates around any other axis, it'll wobble. (And a taco-ed disc will always wobble—it no longer has any axis of symmetry when it's bent out of shape.) Here another visual from the same article:
So that's our goal — we need to make the disc rotate around its own axis of symmetry. The article I linked above is very good at describing wobble. But it doesn't take the next step, explaining exactly what it is about our throws that lead to wobble or a lack thereof. He ends the article saying:
And fixing [wobble] is not rocket science – get the disc aligned with the axis of rotation, and throw it smoothly.
It's not rocket science. But it's still worth explaining well.
Two things* determine how we impart force to the disc
We want the disc to rotate around a certain axis. What determines the axis that the disc will rotate around?
I'll start with a very general answer: the rotation axis is determined by the forces that are coming from our hand which is touching the disc.
That's so general that's it's almost meaningless. Getting into the details, I believe there are really two things that matter in creating a throw with no wobble. I've mentioned them above:
First: the way you grip the disc.
Second: the way your wrist rotates.
The title of this section has the "*" because I'm simplifying slightly. I discuss a few minor complications in the conclusion.
I'd actually like to talk about wrist rotation first. The wrist is a very flexible joint, and there's a bunch of ways we could rotate it.
We could potentially throw a frisbee using a rotation where we first tilt the wrist towards the thumb, and then tilt the wrist towards the little finger. That would be rotating the wrist around this axis:
In an earlier image, I used a red arrow to indicate an axis of rotation. Here, the same red arrow represents the axis of rotation. But it shows up as a red dot, because we're looking at it "from above".
Again, we could throw a frisbee with absolutely no wobble by rotating our wrist around this axis—as long as the combination of our grip and our rotation axis result in the frisbee being spun around its axis of symmetry. This rotation is very roughly what we do throwing a chicken wing.
In a more realistic example for the forehand flick, most throwers are more-or-less rotating the disc around an axis like this one:
Disc/forearm angle
Let's take a quick detour. A number of other throwing guides have talked about the angle the disc makes with your forearm. For example, the Ultiworld article I've linked above has this image:
A video on Jamie Eriksson's JEThrowing.com includes this image:
And on Ryan Lowe's FrisbeeThrows.com, he talks about the disc/forearm in a video analyzing a customer's form, saying:
I can tell, kind of, that the disc is not perfectly in line with your forearm...Just turn that disc so that it's more lined up with the forearm...
I think all of these sources are on the right path, but they seem to just assume that this alignment is good, and don't really explain, biomechanically, why this alignment is a good idea.
Side note to the side note: we need to be careful drawing lines on pictures. The disc might appear mis-aligned with the forearm due to nothing more than the camera angle. Look at these two pictures I took of myself holding the disc:
In the left image, the disc is almost perfectly in line with my forearm. In the right image, there's a noticeable deviation angle. But here's the thing: I didn't move my arm at all between the two photos. I just moved the camera rightward—we can see more of the top of the disc and can see the electrical outlet that was previously hidden behind my forearm.
We shouldn't necessarily trust these images we see of purported angles between the disc and the forearm. Alignment is 3-dimensional, and isn't always captured correctly by a 2-D image.
More on wrist and grip
With that out of the way, let's get back to wrist rotation and grip. In the typical case, like in my diagram above, most people are rotating their wrist around roughly the same axis. But the devil is in the details—I don't think everyone is rotating their wrist around exactly the axis that's perpendicular to their forearm. Instead, different throwers will have slightly different axes of rotation. Like this:
Now let's go back and talk about grips, and then bring it all together. Above, we saw a diagram with just a frisbee. And then we saw a diagram with just a wrist. Putting them together will help understand the importance of grip. Just like people may rotate their wrist around different angles, they'll also grip the disc in different ways, giving it a different orientation with respect to our hand/wrist/arm:
With each of these different angles, the disc's axis of symmetry will be pointing in a slightly different direction:
You can probably guess where this is going: a throw won't wobble if the axis of rotation of our wrist is parallel to the axis of symmetry of the disc. Instead of continuing to draw three superimposed frisbees, let's look at one specific example.
Many people will grip the disc in a way that there's a slight angle between the forearm and the disc, like this:
The disc isn’t aligned with their forearm, but people who do this are still capable of throwing a flick the doesn't wobble — they just need to also rotate their wrist around an axis that's at this same slight angle (like the light blue axis a few images back). This is possible since the wrist has so many possibilities for motion. I know at least a few people who throw like this with no wobble:
Remember those images of the disc lining up with the forearm? If we took someone who threw like this and "fixed" their grip so the disc made an 180 degree angle with their forearm, their throws would wobble more. This is why I stress that wobble is a combination of the way we grip and the way we rotate our wrists. Technically, it's possible for any grip to result in a throw with no wobble, as long as our wrist rotation axis "compensates" for it, and vice versa.
The wrist can rotate lots of ways, but one (I assume) is best
Although I've shown it's possible to throw without wobble even if the disc doesn't line up with our forearm, I believe, along with Jamie Eriksson and Ryan Lowe, that the best throwing motion is one where the disc lines up with our forearm.
Here's where we get into the "just a guy on the internet pretending to understand biomechanics" part of the post (although I do have a degree in mechanical engineering). It’s possible my logic here is flawed. But at least I'll try to make a coherent argument for the disc lining up with your forearm, instead of just assuming it's a good idea.
Basically, I believe the wrist rotation will be the most effective when we can rotate our wrist while it's in a "neutral" position. I'm not an anatomy expert, but it makes a lot of sense that our wrist would "most naturally" rotate along a path where the back of the hand first moves closer to the top of the forearm, and then the palm moves closer to the inside of the wrist — what this Healthline article calls "flexion" and "extension", without radial or ulnar deviation. One reason this type of motion might be best is that it (I assume) uses the biggest, most powerful muscles in the forearm, while the smaller muscles that pull the hand side-to-side just need to provide a steadying presence to keep the neutral deviation.
Here's another way to look at it: in a previous article, I showed how great forehand flicks involve using the arm (both the wrist and the elbow) as a whip. In this understanding, the wrist's role isn't to generate power, but rather to efficiently transfer the power that's generated by the larger muscles further up our arm.
If we're doing this, we want our wrist to be relaxed — in a neutral position. A whip needs to be loose and flexible to transfer energy efficiently — that's why we can make the tip of a whip move so much faster than the tip of an inflexible metal pole of the same length.
But if we distort our wrist from its neutral position when throwing the disc, we’re activating some of those small muscles/tendons/ligaments in the wrist joint to change the angle between our hand and forearm:
And when those tissues are activated, they're in tension—exactly what we don't want since a whip requires flexibility and looseness.
If you're convinced, then the lesson is this:
We want to be able to rotate the wrist in a neutral position
To do that, while also throwing without wobble, we need to line the disc's axis of symmetry up with the wrist's bestaxis of rotation.
In other words, it's better to change our grip so that our wrist can rotate its 'best' way
As a result, the flat plane of the disc will also happen to be lined up with our forearm
Some Closing Thoughts
I'm pretty confident that, geometrically and biomechanically, the biggest determinant of a throw without wobble is what I've described above: the alignment between the axis our wrist rotates around and the axis of symmetry of the disc when it is in our grip. There are some other unwritten assumptions I've made above as well. For example, I'm kind of assuming that our fingers on the inside of the disc are pushing the disc in a direction that matches how our wrist is rotating.
A few other considerations will often come up when throws and wobble are discussed:
First: gripping the disc tighter. In my view, this is often solid advice. I imagine the main effect of gripping the disc tighter is ensuring that the disc doesn't slip slightly in our hand as we go through our throwing motion. If we start out with the "two axes aligned", but the disc slips in our hand as we throw it, we'll end up with a misaligned, wobbly throw. Gripping tighter can fix this. But gripping the disc tightly won't fix our wobble if the wobble is caused by our grip being unaligned.
If our form is good, it's possible to throw a disc with no wobble even if we don't grip it tightly. But a tighter grip will greatly reduce the risk of slight slippage generating wobble.
Second: spinning the disc more quickly. Again, I agree this is good advice. A spinning disc will eventually "smooth out" its own wobble. More spin will also help our throws stay straighter for longer. But elite throws shouldn't need to smooth out their own wobble—it's best to just not let them wobble in the first place.
Third: Having a "smooth" release. People will often say this, although I've never seen someone try to give an explicit definition of what it means. If I had to, I'd say something like this: if our hand is imparting forces to the disc as we throw it, it's possible that (even if our grip/wrist rotation angles are aligned) there are some extra forces being imparted if some little part of the disc is bumping ever-so-slightly against some part of our hand as we're letting go of it.
So, yes, using this definition, I think we should aim for a "smooth" or "clean" release. Though I've never come up with any way to train that (aside from just practicing). Smoothness is theoretically a factor, but my advice is to not worry about it: I think in the vast majority of cases, wobble is caused by the disc & wrist rotation axes being misaligned, not by the edge of the disc catching on our hands.
But I worry that encouraging people to have a "smooth" release often is interpreted to mean something very different. When I hear the phrase "have a smooth release", as an inexperienced frisbee player, it sounds to me like I should change my throwing motion. But after all this time I've spent thinking about, I believe people who are looking for a smoother release would often be better served by changing their grip. I don't think this is easy to realize.
If an inexperienced frisbee player starts with a sub-optimal grip, and then tries to improve their throws by also mis-aligning their wrist rotation, they'll be able to achieve a throw with no wobble. But if they ever want to have elite form, they now have two things to fix instead of one.
I like to think that I've provided a unique and valuable perspective with this article. Others have written about wobble, but I haven't seen another article/video that clearly connects that wobble to the way we grip the disc and rotate our wrist. Others have talked about the angle between the disc and the forearm, but they've mostly just assumed that this alignment is good, while I've tried to explain the underlying logic that makes that alignment a good idea — the alignment of the two axes that reduces wobble and the idea that our wrist (probably) has a "best" way to rotate.
Changing your grip and wrist motion is likely to be a frustrating process. This article may be able to help you unlock the next level of throwing skill, but you're almost certainly going to temporarily get worse before you get better. Consider your relationship with frisbee and whether this is the right investment for you.
Edit (2023-09-19): I later found this YouTube Short which I think is making a similar point:
The commenters there pointed out this video as well:
He suggests it’s OK in ultimate frisbee, but I still think even in ultimate you want to rotate your wrist through its most powerful axis of rotation.
