In-Sync 4

(24 reviews)

In-Sync 4 is recommended to help support healthy muscle function, immune system, blood cell (oxygen) production and hair coat. Key ingredients include lysine and methionine for muscle development; thiamine, niacin, riboflavin, and vitamin B12 for red blood cell production; natural vitamin E and other antioxidants for immune system function; and magnesium, selenium, and DMG for muscle function… Read More

Current Stock:
Adding to cart… The item has been added

In-Sync 4 is recommended to help support healthy muscle function, immune system, blood cell (oxygen) production and hair coat. Key ingredients include lysine and methionine for muscle development; thiamine, niacin, riboflavin, and vitamin B12 for red blood cell production; natural vitamin E and other antioxidants for immune system function; and magnesium, selenium, and DMG for muscle function. In addition, key ingredients such as magnesium, vitamin E, lysine, and DMG may also help manage muscle discomfort.





Magnesium (Mg) is a macro mineral that is frequently recommended for a wide range of equine health conditions. Magnesium helps to maintain normal muscle and nerve function, a healthy heart, healthy immune system and strong bones. Magnesium aids to regulate blood sugar levels, promotes normal blood pressure, and known to be involved in energy metabolism and protein synthesis. Since a symptom of magnesium deficiency is agitation or anxiety, it is included in many calming supplements.

DMG (Dimethylglycine) is a naturally occurring substance in the body and in many foods, but in low levels. Supplementing with this ingredient makes additional DMG available to cells throughout the body, where it is involved in energy production processes that use oxygen. DMG is used to help support muscle function, a healthy immune system, metabolism and serve as an antioxidant.

Methionine is an amino acid that must be provided in the diet since the body cannot create enough of its own. This means if it is not present in adequate amounts it limits the body's ability to make protein. Methionine can be converted by the body into another sulfur-containing amino acid, cysteine. Because the concentration of both these amino acids is highest in hoof and hair, methionine is often included in hoof health supplements. 

Lysine is an amino acid and the only one for which a requirement in the horse has been established by the NRC and used for the biosynthesis of proteins. This amino acid is often the key to improving protein availability and healthy muscle function.

Vitamin C (Ascorbic Acid) is an antioxidant that plays a role in helping combat harmful free radicals. Vitamin C is an antioxidant that helps protect the tissues of the body and also important in the production of connective tissues like tendons and ligaments.

Zinc (Zn) is a micromineral involved in over 100 enzyme systems ranging from support of connective tissue formation and antioxidants to carbohydrate metabolism and immune system function. It is most recognized for its role in healthy skin and hooves.

Copper (Cu) is a micromineral that aids in the production of normal connective tissues including tendons, ligaments, cartilage and bone. As a component of many enzyme systems, it is also involved in making iron available to the body for blood, in producing skin and coat pigments, in proper nerve signaling and in repairing antioxidants.

Selenium is a trace mineral that along with vitamin E function together to help to protect body tissues from free radical damage that occurs during oxidation (the conversion of feedstuffs into energy). While some parts of the country have high levels of selenium in their soil and therefore the plants that grow there, selenium deficiency is not uncommon and reported in many states. Therefore, most horses may require supplementation to meet the NRC requirement of 1-3 mg/day, depending on activity level. *NRC upper safe limit approx. 20 mg/day in total diet.

Vitamin A is well known for its role in supporting healthy vision, immune function, and skin/coat. However, it is also needed for respiratory health, reproduction, soft tissue and normal skeletal development in young growing horses and exercising horses that are remodeling bone. 

Vitamin E (Natural):  Natural E is approx. 2.5 times more bioavailable than synthetic vitamin E (4,000 IUs natural vitamin E approximates 10,000 IUs of synthetic vitamin E). Most studies/research indicate 8,000 IU’s -10,000 IU’s (or approx. 3,000-5,000 IU of Natural Vitamin E) during/post therapy for immune support. Vitamin E is considered the most important antioxidant and works closely with selenium to protect the body from the oxidative stress of exercise and illness. Found in high amounts in fresh pasture, levels begin to decay the moment pasture is cut for hay. That is why any horse that does not have access to grass, regardless of its activity level or health, would be a candidate for vitamin E supplementation. Horses are not very efficient in storing vitamin E and deficiency may be accelerated if the diet is deficient in selenium.

Vitamin D (Calciferol) plays an indirect role in bone growth and maintenance by managing the levels of calcium (Ca) in the body. It assists in the absorption of Ca from the intestine, the movement of Ca into and out of bone, and the amount of Ca excreted by the kidneys.

The Vitamin B family is made up of several compounds that support many important roles in the body: protein, fat and carbohydrate metabolism; energy production; proper nerve cell transmission, reproduction, and division (especially rapidly dividing ones such as red blood cells). B vitamins include thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), folic acid (B9), cyanocobalamin (B12), choline, biotin, inositol and others are sometimes referred to as B-vitamins. For most of the B-vitamins, microorganisms in the large intestine make all the horse needs. Only thiamine and riboflavin have NRC dietary requirements. However, research suggests B-vitamin supplementation may be beneficial to horses with little access to fresh pasture and/or during any periods of stress (training, injury, travel, etc.)

Active Dry Yeast:  Supports enzyme activity for fiber digestion in the hind gut and provides a direct source of nutrients to nourish good bacteria. Stabilizes digestive flora during periods of stress for overall health and performance.

Probiotics are live microorganisms (bacteria and yeast) that help promote healthy digestive function and support a healthy immune system. Often referred to as ‘good bugs’ they help break down ingredients/contents that the body normally can't, and help inhibit ‘bad bugs’ from growing.

Is this okay for a pregnant mare?

MVP: The safe use of this supplement in pregnant or lactating mares has not been specifically tested. We always recommend seeking your veterinarian’s advice before adding any new supplements or making changes to your mare’s diet.

Is the Vitamin E natural or synthetic?

MVP: In-Sync 4 contains d-Alpha Tocopheryl which is the natural form of vitamin E.

My horse is currently on vitamin e and selenium. Does this have enough it to replace that while getting the added benefits of the muscle recovery?

MVP: Yes, In-Sync 4 provides 2000 IU of natural vitamin E and 1 mg selenium per 2 ounce serving along with ingredients such as magnesium, lysine & amino acids for muscle recovery support!

I see information regarding the ingredients but have there been any independent lab tests done to verify that the ingredients quantities match the label?

MVP: As a founding member of the National Animal Supplement Council (NASC), our manufacturing facility adheres to strict manufacturing guidelines by following GMPs (Good Manufacturing Processes) and FDA procedures to ensure quality and consistency of products. We implement a variety of quality assurance practices starting from development all the way through every order that leaves our facility to support the quality and accuracy of products. All raw materials must be approved for use according to quality assurance and inspection processes. We also utilize a variety of laboratory analyses to assess the potency and purity of raw materials.

  • 5
    In-Sync 4

    Posted by Christina Swan on 26th Feb 2024

    I feel confident working my mare knowing she will not experience muscle issues while on this product with proper conditioning.

  • 5
    In-sync 4

    Posted by DeAnna Weippert on 29th Jan 2024

    I’m very happy with this product My mare was grossly over weight and could not process her carb intake. I started to really notice changes in her overall weight and attitude as the terrible soreness in her feet start to change or decrease within the first 60 days of feeding her In-sync 4 as well the recommended diet changes from MVP

  • 5

    Posted by Shari Pachta on 9th Jan 2024

    My mare got diagnosed with MYHM as a five year old. This supplement has literally changed her life. It has helped her muscle function and ability to move around hugely!! She will for sure be on it the rest of her life! She also eats it with ease. She loves it!

  • 4

    Posted by Tim Yoder on 12th Dec 2023

    In-Sync 4 makes them muscle up and makes their coats nice and shiney. I did use it on a pony with CPR and it seemed to help him stay limber back up.

  • 5

    Posted by Julia Prebula on 25th Oct 2023

    In-Sync 4

  • 5

    Posted by emily bolda on 12th Oct 2023

    I bought this product for a young 3 yr old on track for 2024 futurity. It’s only been 2 ish weeks but i notice a big difference already in recovery / soreness. This mare use to walk away from me in the pasture. Vet and I suspected something but she flexed and checked out fine. After being on this she comes right up to me, enjoys working and has worked out of some of our stiffness issues on the right side. Can’t wait to see what it does for overall muscle growth

  • 5
    #1 supplement for my...

    Posted by mary bleeker on 30th Aug 2023

    Every horse that I have is on this. Has everything I feel they need. Their top line is always strong

  • 5

    Posted by Taylor Floyd on 2nd Jun 2021

    My 4 year old N/P1 QH mare is very symptomatic. I had seen a lot about people using Insync-4 and thought I’d give it a try for her. And let me say, it was a game changer for us. She has mild symptoms when the weather changes but other than that she is doing amazing. She is solid muscle too, we are finally able to get her first rides done soon. She is happy and now runs and plays in the pasture instead of standing and hurting.

  • 5
    In sync 4

    Posted by Skylar Eisinger on 2nd Feb 2021

    Needed to add muscle to my 4 year old Futurity mare...after 2 months she’s one solid mass of muscle and winning me money! Over $12,000 in 2 months