Equine obesity is a serious welfare issue right now, and it’s every horse owner and rider’s job to play their part in slimming down waistlines and helping equines everywhere become healthier.

The harder your horse works, the more energy he uses, but clearly a horse can’t gallop for 20 minutes. On the other hand, he can walk for a long time, but walking’s not the greatest way to burn calories.

Unfortunately, there is no easy way to count calories with your horse and know exactly what he’s burning when exercising. However, there are plenty of ways you can get him working to encourage weight loss, as Dr David Marlin, a scientific and equine consultant with more than 25 years’ experience in physiology and biochemistry, explains.

Influential factors

How hard your horse is working can depend on a number of different factors:

1 Duration: Obviously the longer your horse is exercising, the more calories are burned.

2 Surfaces: Soft surfaces are harder work for your horse than hard surfaces.

3 Terrain (hills): The least amount of energy is used on a slight downhill slope. Uphill work can significantly increase energy consumption. For example, trotting up a 5% incline is 1.6 times harder than trotting at the same speed on the flat. A 10% incline is over twice as hard as the same speed on the flat.

4 Rider weight: Exercising with a rider is harder work than without. A heavier rider requires the horse to use more energy still.

5 Weather: If you exercise in the warmer part of the day your horse will use more calories than if you exercise in the cool of the morning.

6 Direction: Turning uses more energy than exercising in straight lines. The tighter the turn, the more calories are used.

7 Pace: Varying the pace/speed (ie, speeding up and slowing down) uses more energy than exercising at a constant speed.

8 Transitions: Transitions between gaits use more energy than staying within a gait.

9 Gait: Each horse has a speed within each gait where he’s at his most efficient — ie, he uses the least amount of energy. A slow or fast walk or a slow or fast trot use up the most energy compared to a walk or trot speed in the middle of a horse’s speed range in each gait.

Best calorie-burning exercise

The best way to burn calories is to use a combination of trotting and cantering. So, per minute of exercise, trotting (at 3.5m/s or 210m/min, or 7.8mph or 12.6kph) uses 2.3 times as much energy as walking (at 1.5m/s or 90m/min, or 3.4mph or 5.4kph).

Slow cantering (at 7m/s or 420m/min, or 15.7mph or 25.3kph) uses up to twice as much energy per minute compared with trotting.

Having said that going fast or slow within walk and trot can mean that your horse uses up more energy, this can also increase the risk of injury and so it is not advisable.

Don’t push too soon

If your horse is overweight, it’s really important that you aren’t tempted to just get on and start working him hard. An overweight horse’s joints, tendons and ligaments are already under increased stress due to his excess weight. The weight of a rider and hard work could easily lead to injury.

For this reason it’s advisable to start with lungeing and walking in-hand. Ridden work at walk and trot can then be introduced slowly and you can build up to both ridden and lunge work each day — perhaps riding in the morning and lungeing in the evening.

The size of the lunge circle determines how hard your horse has to work. The smaller the circle, the more calories will be burned, but this can also increase the risk of injury.

Exercise in a rug

Rugs can also be used to make horses work a little harder without putting more strain on tendons, ligaments and joints. In the same way that in warm weather your horse will have to work harder, exercising wearing a rug will increase the effort he makes.

However, this must be done with care to ensure that your horse doesn’t get overheated, and he may require additional electrolytes in his feed if he sweats more than usual. Your horse’s breathing is the best guide to his temperature — blowing hard is the sign of a hot horse.

Monitor his heart rate

The most reliable way to know how hard your horse is working so that you can avoid working him too hard is to use a heart rate monitor. The harder he’s working, the higher his heart rate will be.

So, if your horse appears to be telling you that he can’t work any harder but his heart rate is only 120bpm (beats per minute), then you know he’s probably being lazy! If, on the other hand, his heart rate is 200bpm, then you are probably working him too hard for a weight loss programme. Ideally, you want to be working for prolonged periods in the 120-160bpm range.

A heart rate monitor can also be an excellent guide for when to stop exercising. If you’ve been out hacking for 40 minutes and you stop, if your horse’s heart rate isn’t back down below 100bpm within two minutes, then he’s done enough for that session and it’s time to walk home.

Track and field systems

If your horse is turned out during the day, then a track system is worth considering if you have the facilities and option to set one up. In some research, horses on a track system have been shown to cover greater distances.

If your horse is turned out (or even stabled), don’t be tempted to over-rug him as this will reduce the amount of energy he has to use to keep warm.

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