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Orders under 1lb or to APO/FPO & PO Box destinations: These orders will ship with USPS and typically take 1 to 2 days longer than the Standard Delivery estimate. Free Shipping Offers: Only valid within the contiguous USA. Future subscriptions will renew with free shipping if the renewal amount is $49 or higher otherwise shipping will cost $7.95.
 

Science in Sport

99 results
  1. SiS Tryout Pack
    Earn 10% Credit
    SiS Tryout Pack

    12 Pack

    Review Rating: 4.7 /5
    (24 reviews)
    $32.00
    Out of Stock
  2. 10 for $10 SiS Go Isotonic Energy Gels
    10 for $10 SiS Go Isotonic Energy Gels

    10 Pack

    Review Rating: 4.7 /5
    (1147 reviews)
    $10.00
    $19.12
    Save 48%
  3. SiS Beta Fuel Chews
    SiS Beta Fuel Chews

    3x Lemon + 3x Orange / Variety Pack

    Review Rating: 4.8 /5
    (148 reviews)
    $19.99
  4. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Tutti Frutti / Box of 30

    Review Rating: 4.6 /5
    (824 reviews)
    $49.99
  5. SiS GO Energy + Electrolyte Gel
    SiS GO Energy + Electrolyte Gel

    Raspberry / Box of 6

    Review Rating: 4.5 /5
    (317 reviews)
    $11.50
  6. SiS Beta Fuel
    SiS Beta Fuel

    Orange / Box of 15

    Review Rating: 4.5 /5
    (116 reviews)
    $45.00
  7. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Lemon and Lime / Box of 30

    Review Rating: 4.6 /5
    (824 reviews)
    $49.99
  8. SiS Hydro Tablets
    SiS Hydro Tablets

    Lemon (Best By 6/31/25) / 20 Tablets

    Review Rating: 4.7 /5
    (457 reviews)
    $7.20
    $12.00
    Save 40%
  9. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Orange (Best By 6/30/25) / Single Serving

    Review Rating: 4.5 /5
    (263 reviews)
    $1.40
    $2.00
    Save 30%
  10. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Citrus / Box of 6

    Review Rating: 4.5 /5
    (263 reviews)
    $11.50
  11. SiS GO Energy + Electrolyte Gel
    SiS GO Energy + Electrolyte Gel

    Raspberry / Box of 30

    Review Rating: 4.5 /5
    (317 reviews)
    $55.00
  12. SiS Beta Fuel Chews
    SiS Beta Fuel Chews

    Orange / 6 Pack

    Review Rating: 4.8 /5
    (148 reviews)
    $19.99
  13. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Orange / Box of 30

    Review Rating: 4.6 /5
    (824 reviews)
    $49.99
  14. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Double Espresso / Box of 30

    Review Rating: 4.5 /5
    (263 reviews)
    $55.00
  15. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Orange / Box of 6

    Review Rating: 4.5 /5
    (263 reviews)
    $11.50
  16. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Citrus / Box of 30

    Review Rating: 4.5 /5
    (263 reviews)
    $55.00
  17. SiS GO Energy + Electrolyte Gel
    SiS GO Energy + Electrolyte Gel

    Raspberry / Single Serving

    Review Rating: 4.5 /5
    (317 reviews)
    $2.00
  18. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Cherry / Box of 30

    Review Rating: 4.6 /5
    (824 reviews)
    $49.99
  19. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Tropical / Box of 30

    Review Rating: 4.6 /5
    (824 reviews)
    $49.99
  20. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Apple / Box of 30

    Review Rating: 4.6 /5
    (824 reviews)
    $49.99
  21. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Cherry / Box of 6

    Review Rating: 4.6 /5
    (824 reviews)
    $11.00
  22. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Orange / Box of 30

    Review Rating: 4.5 /5
    (263 reviews)
    $55.00
  23. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Berry / Box of 30

    Review Rating: 4.5 /5
    (263 reviews)
    $55.00
  24. SiS Beta Fuel Chews
    SiS Beta Fuel Chews

    Lemon / 6 Pack

    Review Rating: 4.8 /5
    (148 reviews)
    $19.99
  25. SiS GO Electrolyte Drink Mix
    SiS GO Electrolyte Drink Mix

    Lemon Lime / 40 Servings

    Review Rating: 4.6 /5
    (136 reviews)
    $40.00
  26. SiS GO Electrolyte Drink Mix
    SiS GO Electrolyte Drink Mix

    Raspberry / 40 Servings

    Review Rating: 4.6 /5
    (136 reviews)
    $40.00
  27. SiS GO Electrolyte Drink Mix
    SiS GO Electrolyte Drink Mix

    Orange / 40 Servings

    Review Rating: 4.6 /5
    (136 reviews)
    $40.00
  28. SiS Hydro Tablets
    SiS Hydro Tablets

    Pink Grapefruit (Best By 6/31/25) / 20 Tablets

    Review Rating: 4.7 /5
    (457 reviews)
    $7.20
    $12.00
    Save 40%
  29. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Pineapple / Box of 30

    Review Rating: 4.6 /5
    (824 reviews)
    $49.99
  30. SiS REGO Clear Recovery
    SiS REGO Clear Recovery

    Peach / 10 Servings

    Review Rating: 4.6 /5
    (12 reviews)
    $29.99
  31. SiS Protein Bar
    SiS Protein Bar

    Milk Chocolate and Peanut / Box of 12

    Review Rating: 4.5 /5
    (343 reviews)
    $32.99
  32. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Tutti Frutti / Box of 6

    Review Rating: 4.6 /5
    (824 reviews)
    $11.00
  33. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Orange / Box of 6

    Review Rating: 4.6 /5
    (824 reviews)
    $11.00
  34. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Tropical / Box of 6

    Review Rating: 4.6 /5
    (824 reviews)
    $11.00
  35. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Lemon and Lime / Box of 6

    Review Rating: 4.6 /5
    (824 reviews)
    $11.00
  36. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Apple / Box of 6

    Review Rating: 4.6 /5
    (824 reviews)
    $11.00
  37. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Double Espresso / Box of 6

    Review Rating: 4.5 /5
    (263 reviews)
    $11.50
  38. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Citrus (Best By 6/30/25) / Single Serving

    Review Rating: 4.5 /5
    (263 reviews)
    $1.40
    $2.00
    Save 30%
  39. SiS GO Energy + Caffeine Gels
    SiS GO Energy + Caffeine Gels

    Berry / Box of 6

    Review Rating: 4.5 /5
    (263 reviews)
    $11.50
  40. SiS Bake Energy Bars
    SiS Bake Energy Bars

    Strawberry / Box of 12

    Review Rating: 4.7 /5
    (93 reviews)
    $24.99
  41. SiS Bake Energy Bars
    SiS Bake Energy Bars

    Lemon / Box of 12

    Review Rating: 4.7 /5
    (93 reviews)
    $24.99
  42. SiS Hydro Tablets
    SiS Hydro Tablets

    Strawberry and Lime / 20 Tablets

    Review Rating: 4.7 /5
    (457 reviews)
    $12.00
  43. SiS Go Isotonic Energy Gels
    SiS Go Isotonic Energy Gels

    Orange / Single Serving

    Review Rating: 4.6 /5
    (824 reviews)
    $1.99
  44. SiS REGO Clear Recovery
    SiS REGO Clear Recovery

    Peach / Box of 15

    Review Rating: 4.6 /5
    (12 reviews)
    $59.99
  45. SiS HYDRO+
    SiS HYDRO+

    Variety Pack / Variety 6-Pack

    Review Rating: 5 /5
    (3 reviews)
    $12.00
  46. SiS REGO Clear Recovery
    SiS REGO Clear Recovery

    Raspberry Cranberry / 10 Servings

    Review Rating: 4.6 /5
    (12 reviews)
    $29.99
  47. SiS Bake Energy Bars
    SiS Bake Energy Bars

    Variety Pack / Variety 6 Pack

    Review Rating: 4.7 /5
    (93 reviews)
    $13.50
  48. SiS Protein Bar
    SiS Protein Bar

    Cookies and Cream / Box of 12

    Review Rating: 4.5 /5
    (343 reviews)
    $32.99