To appreciate what javelin gold medalist Neeraj Chopra achieved in Tokyo, consider this: He threw the weight of nearly five cricket balls at a starting speed of about 100 kmh across a length of more than four cricket pitches.

The men’s javelin weighs a minimum 800 gm, while the cricket ball typically weighs 163 gm. The length of a cricket pitch is 20.12 metres. Neeraj’s best throw in the final was 87.58 metres.

That is just the end result. What went into the throws is a beguiling combination of biomechanics which might be better explained by Virus – the overly strict engineering college professor – in the 2009 Hindi film 3 Idiots.

On the face of it, javelin is a simple sport. Grab spear, run and throw. But when it is broken down, its complexity reveals itself.

The approach itself has two components – the run-up and crossover steps. Then there are the load-up and release, which comprise concepts such as ‘angle of attitude’ and ‘angle of velocity vector’.

That is why we may need Virus to explain it to us. Till such time as we hear back from him, we will go over the different parts of the javelin throw chain.

The grip: There are three types of holds. The simplest is the American grip, with thumb and forefinger doing much of the supporting behind the grip cord. There is the Finnish grip, with the forefinger extended to support the shaft, and one which Neeraj appears to use. The third is the ‘V’ grip or ‘the claw’, where the javelin rests in the ‘V’ between the forefinger and middle finger.

The run-up and crossover: The thrower sprints about 15 steps, as Neeraj did in Tokyo, to generate momentum. This is followed by two or three side-on steps, called the crossover steps. According to an article on theconversation.com by Mike Barber, a biomechanics expert currently with Athletics Australia, “The second-last crossover step, known as the impulse step, is slightly exaggerated to allow the thrower to land with their weight over their back foot, a similar movement to a cricket fast bowler.”

Components of javelin throw: Notice the American grip of the thrower and the exaggerated crossover step as he prepares to launch the javelin.

The final or delivery step: This is where momentum created by the run transfers like a current from the athlete’s body to his limbs and then the javelin. Barber calls it a “whip-like transfer of energy from the hip to shoulder to elbow to javelin.”

Barber writes, “A force six to eight times the athlete’s body weight is created at front foot contact. A bent or ‘soft’ knee will result in a loss of energy transfer, so it’s important for javelin throwers to develop the leg and ankle strength to handle these large forces.”

You may have seen clips of Neeraj’s punishing workout where he kangaroo-jumps over hurdles, front-on as well as side-on. They are to build leg strength.

The throw: The moment has arrived. Let it fly. But it is not that simple. For optimal results, the ‘angle of release’ for a javelin is between 32º and 36º.

Wait, there are other angles to keep track of. The flight path and distance of the javelin depends on the ‘angle of attack’. That is the difference between the ‘angle of attitude’, which is the orientation of the javelin to the ground, and the ‘angle of velocity vector’, which is the flight path of the javelin’s centre of mass (not the tip).

Once you have got that down, thanked the Viru Sahastrabuddhe (Virus) of your school, you throw. And mutter, “Now, little Starling, fly, fly, fly,” if you are a Silence of the Lambs fan.

Sometimes, coaches simplify the advice by telling their wards to “throw through the tip”.

Representative image of the 1940 athletics championship in Austria. There are many angles to keep track of in javelin throw, including the optimum ‘angle of release’ which is between 32º and 36º. (Image: Austrian National Library via Unsplash)

The portal coachup.com has another lucid piece of advice on the throw.

“Make sure your elbow is high when you coil back to release the javelin,” it says. “Your throwing hand should be as high as possible. The point of release for the javelin should be in front of your planted foot. Remember to follow through completely, or you may lose distance in your throw.”

Unlike a cricket bowler, who can follow through beyond the crease, the thrower cannot overstep the line. That is why even at Olympic level, there are so many infringements. Neeraj himself fouled twice in the final. But by then, he had done enough.