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Opti Muscle™

Support for hard working or vulnerable muscles

24 reviews. 4.8 / 5
Melanie - 25/02/2024 08:30
As good as ever.  I have been using this product for a couple of years now.
Susan - 04/01/2024 18:39
My horses look fabulous on this product all have top muscular top line and stamina for endurance
Melanie - 21/09/2023 15:48
Great product.  Quick and efficient service.   Keeps my horses in good condition.
Kate - 03/05/2023 14:26
Seems to have improved my dressage horse’s strength and stamina, this is the second time I have tried it and each time noticed an improvement
Tanya - 15/12/2022 07:32
An extra boost for any horse
Zoe - 10/02/2022 15:59
too early to tell yet but he doesnt mind the taste!
Lorraine - 15/07/2021 10:13
Excellent product and has helped my elderly horse to keep competing
judith - 16/06/2021 20:13
For reasons given in initial comment.
Debbie - 02/05/2021 21:16
One word says it all !! From order to delivery and the products themselves “amazing “ Thankyou so much
Trusted Feefo Customer - 14/04/2021 23:04
I have used this supplement before for a young horse that I had great difficulty in getting to keep weight and muscle on. She is now like a different horse altogether!
This time, I have purchased for an elderly horse, which has lost a lot of condition (but has clean bill of health from vet). I am hoping to build him up a little before weaning him back onto grass.

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Nutrition Information

Opti Muscle™ supports muscle health by providing Vitamin E, Selenium, Magnesium and B Vitamins that are essential for optimum nerve and muscle function.

Vitamin E and Selenium are important nutrients that act as antioxidants, which play an important role in maintaining healthy cell membranes and normal muscle function through their free radical neutralising action. Magnesium supports nerve function and muscle relaxation, allowing horses and ponies to work with greater flexibility. Additionally, B vitamins are essential for the formation of coenzymes and enzymes necessary for cell metabolism, helping your horse or pony to utilise energy sources effectively. Helping to keep cells healthy whilst supporting optimum metabolism will help to maintain muscles in a healthy condition and will aid horses and ponies to work more effectively and promote correct muscle development.


Grass meal, Maize meal, Magnesium oxide (4.4%).


  Additive number per kg 
BHT (Butylated hydroxytoluene) E321 0.3 g
Vitamin E (all rac-α-tocopheryl acetate) 3a700 54,803 iu
Vitamin K (Menadione sodium bisulphate) 3a710 300 mg
Thiamine (Thiamine hydrochloride) 3a820 1,499 mg
Riboflavin  3a825i/3a825ii 899 mg
Pyridoxine (Pyridoxine hydrochloride) 3a831 899 mg
Vitamin B12 (Cyanocobalamin)   9 mg
Biotin 3a880 30 mg
Niacin 3a314 200 mg
Folic acid 3a316 599 mg
Pantothenate (Calcium pantothenate) 3a841 1,798 mg
Choline (Choline chloride) 3a890 2,997 mg
Trace elements    
Selenium (Sodium selenite) 3b801 37 mg 



Crude protein 11.2%
Crude oils & fats 8.0%
Crude fibre 12.0%
Crude ash 14.5%
Acid insoluble ash 5.7%
Sodium 0.2%
Starch  17.1%
Sugar  6.0%

Feeding Guide

Weight of Horse/Pony

Amount per day

Maintenance / Light work  

Amount per day      

Medium work             

Amount per day

Hard work                      

Up to 250kg ½ scoop ¾ scoop 1 scoop
250kg - 400kg ¾ scoop 1 scoop 1 ½ scoops
400kg - 600kg 1 scoop 1 ½ scoops 2 scoops
Over 600kg 1¼ scoops 2 scoops 2 ½ scoops


1 level (50ml) scoop of Opti Muscle™ weighs approximately 20.5g

Horse Workload Guide

  • Maintenance/light work: light hacking 1-3 times per week, light schooling, occasional competitions
  • Medium work: 30-60 minute schooling sessions or 1-2 hour hacks daily, riding club competitions
  • Hard work: extensive schooling sessions, regular endurance, dressage or showjumping competitions

Horses experiencing episodes of tight, sore muscles can be fed Opti Muscle™ at the hard work rate for up to 2 weeks.

If you are unsure about your horse's workload please call 0800585525 to speak to an advisor.

Feed supplements should be fed according to body weight. Introduce to the horses diet gradually, splitting between feeds (when applicable).

Opti Muscle™ is a complementary feeding stuff for equine animals. Feedmark uses nothing in the formulation of this product that contravenes competition rules.