In a sense, tension is a spectrum, varying from mild tension to escalated explosive behaviours such as bucking and bolting. The alarming signs, subtle signs of tension, often go unrecognised by riders. Raised head position, hollowing of the back and quickening of the legs are all forms of mild expression of the flight response. They all build upon tension, the first sign of the horse utilising their natural survival mode - the flight response.
Tension builds up. Think of a bottle of soft drink - if you open a still bottle it's fine. If you shake it just a little, it starts creating more pressure inside of the bottle. Shake it some more and it creates more pressure. Open it now and the bottle will be no longer able to contain it. The content will now come out in an explosive manner and keeps coming until there's nothing left. This can serve as an analogy when it comes to tension in horses.
There is several components that can contribute to tension. Ill fitting tack that causes discomfort and pain is not uncommon. Horses that are not responsive to aids and therefore are a subject to eg a constant nagging leg aid, use of spurs and / or heavy rein pressures are the most likely candidates for tension building up whilst riding. Combine these two and the pressure inside of the bottle starts building up ..
Another very common cause for tension whilst riding is use of contradictory aids. This meas using two or several aids to create opposite responses at the same time. A bit like accelerating a car whilst applying the breaks on at the same time.
A perfect horse and rider specific example of this - contradictory aids - is when the rider applies a simultaneous leg and rein aid with the intention to create a situation where the horse is "driven off the leg aid towards the rein" and/or pulled into false collection by forcing the horse to a particular outline whilst asking the horse move forward of the leg aid. This puts the horse in a biomechanically impossible situation ( think of the car analogy ) which in turn will manifest as visible tension in majority of horses - a common cause for a variety of problems and training not moving forward as per planned.
What can we do to eliminate tension in a ridden horse?
Firstly we must understand the task we are asking the horse to do - from HIS point of view. It is helpful to ask yourself a few questions such as:
Are we setting our horses up for success - Is what are trying to achieve appropriate for the level of training the horse and the rider are at? Are we training our way up gradually and applying one new element at the time and not flooding the horse with a new, difficult task that involves more than one unfamiliar component at one time?
Does the horse understand the aids and responds accordingly? //Remember that all responses are trained responses, the horse does not know how to respond correctly by default//
Are we training with the aim that the horse responds to the lightest aids possible and is not subjected to constant heavy pressures from our aids and therefore is free from pain and discomfort?
Are we clear and consistent in our application of the aids and not asking for two opposing things at once - example would be applying leg and rein aid at the same time.
Is the timing of the release of aids accurate? Can the horse control the outcome and remove the pressure as soon as he gives the right response?
Tension is an expression of the Flight Response.
Horses communicate with us via behaviours. If you feel your horse is becoming tense it's good to stop and think of all the potential causes and work towards eliminating them.
Understanding and eliminating the causes of tension increase performance, improve both, welfare of horses and rider safety.