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Opti Muscle™

Support for hard working or vulnerable muscles

22 reviews. 4.8 / 5
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.
Trusted Feefo Customer - 27/01/2021 19:19
Works a treat on my youngstee
Lorraine - 11/01/2021 11:19
It has helped my veteran maintain muscle
Lorraine - 19/11/2020 11:08
Very good product to assist with muscle recovery
Rebecca - 11/06/2020 13:35
Palatable and contains everything he needs to help his PSSM
Susan - 11/06/2020 11:19
My Endurance horses look in great condition with using Opti Muscle.
They have to work hard so using this product I know their system is well supported.
Trusted Feefo Customer - 18/12/2019 14:28
quick international delivery.  I am sure the product will be as good as the other Feedmark products
George - 11/12/2019 13:33
Very nice
Hannah - 30/10/2019 09:57
Seems to work well for my mare . She’s happy to eat it And looks good on it!
Susan - 23/10/2019 22:10
My endurance horses perform well as they need this product to repair their muscles after a hard ride which can be up to 160kms. Have won best condition the next day so must be doing something to keep them in tip top condition
Hannah - 18/09/2019 13:27
Works well for muscle problems in my mare
Pauline - 07/07/2019 08:06
It’s too early to tell what effect this has had
Lavinia - 05/06/2019 10:53
Because it's the 1st time I've purchased it and I haven't been feeding it long enough to see the benefits!!
Trusted Feefo Customer - 04/04/2019 09:22
Only product that has stopped my mare tying up!
Glynis - 15/08/2018 22:40
Regular purchase. Product expensive and no discount code even though I called and requested one
Trusted Feefo Customer - 20/10/2017 00:31
I have only just started using this but I am sure I will be pleased with the result as I am with all feedmark products I have tried

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.