Spirulina
Spirulina is an algae that is rich in protein, essential fatty acids, and phytochemicals.  Only two studies have tested spirulina in an exercise setting and both have shown to increase exercise performance and other health outcomes (ex. antioxidant status).  More studies are needed before strong conclusions are made and recommendations can be given.

Succinate
Succinate is a compound found in the TCA cycle (tricarboxylic acid or Krebs cycle), which is a metabolic pathway that is used for the majority of energy production.  The hypothesis is that increasing the amount of succinate in the TCA cycle will increase the efficiency of energy production.  In one study that investigated the effects of 1000 mg succinate/day in conjunction with many other compounds for 3 weeks, there was no increase in certain blood metabolites or in cycling performance.  Studies with other TCA cycle intermediates have also not been able to show performance benefits.  There is currently no evidence that succinate can improve performance.

Sucrose
Sucrose (table sugar) is a compound comprised of one glucose molecule and one fructose molecule.  Carbohydrates that are absorbed at a moderate to high rate, like sucrose, have been shown to be particularly effective fuel sources during exercise and, additionally, tend not to cause gastrointestinal discomfort.  Sucrose specifically, because it is half glucose and half fructose, can be absorbed and metabolized faster than fructose or glucose alone.

Key practice applications
  • Spirulina has only recently garnered interest in the sports community and more studies are needed before any recommendations can be made.
  • Succinate and other TCA cycle intermediates are failing to show benefits in sports performance.
  • Sucrose may provide value to sports performance.  However, since products containing sucrose often contain little to no other nutrients (vitamins, minerals, fiber, etc.), sucrose is only recommended before and during exercise and not in place of any components in a healthy diet.

Key search terms for this article (5-7 terms): spirulina, succinate, sucrose, TCA cycle, Krebs cycle, sugar