Non-steroidal anti-inflammatory drugs in sport

 

 

By: Nur Hasanah Ruslan

 Sports Science Unit

 

 

 Non-steroidal anti-inflammatory drugs (NSAIDS) have the  property of cyclo-oxygenase inhibition (Katzung et al). The  most common NSAID is acetylsalicylic acid or aspirin  Ibuprofen, Naproxen, Indomethacin, Piroxicam, Flurbiprofen and Diclofenac. According the properties of NSAIDs, this drug are commonly used in sport for treatment of acute athletic injuries, often for analgesic purposes and also to support enhanced healing . Specifically, NSAIDs are not recommended in the treatment of completed fractures, stress fractures at higher risk of nonunion, or in the  chronic muscle injury. Use of NSAIDs may be more appropriate in the management of acute ligament sprains, muscle strains, tendinitis, and eccentric muscle injury .

NSAIDs are used primarily for reducing the pain, heat, swelling and redness that  associated with inflammation  (Almekinders et al.,1993).NSAIDs have been shown to delay  the healing in all the soft tissues, including muscles, ligaments, tendons, and cartilage. NSAIDs  delay healing injuries significantly, even in muscles having  more capillary density  due to decrease in  DNA synthesis  for fibroblast cells proliferation.

Many studies are conducted to monitor  the effects of NSAIDs uses in influences the physiological parameter.But the previous studies, fail to  observe any significant effect on sport performances (Roi  et al.,1994).Other studies   found there is  no  effect on glucoregulatory mechanism  with single dose of aspirin( DeMeersmen et al., 1988) .  Olsen et al (1999) showed  that there was no difference in the control and NSAIDs  groups of different  exercise intensity  of 25%,50 % and 70% of VO2 max .

 Wharam et al (2005) showed  that NSAIDs are commonly used by  endurance athletes. It is a    high risk  factor for hyponatremia  and can  cause alteration of renal function.  Wharam et al showed high rate  of NSAID use, resulted in  low  incidence of hyponatremia  . The reason behind,  is  still unknown.Actually maintance of renal function is very  important to cop with  many physiological changes during exercise  to achieve highest sport performences.

 Trappe  et al (2001) proved that both Ibuprofen and Acetaminophen suppress the protein synthesis  in skeletal muscle after eccenteric resistence exercise by work through a common mechanism to influence protein metabolism in skeletal muscle.Long term used of  both drugs  exhibit inhibition  the hypertroping  to resistance training . Tokmikidis et al (2003)  exhibited  that intake of Ibuprofen can decrease muscle soreness induced by eccenteric exercise but Ibuprofen does not assist in restoring muscle function.So it cannot  contribute to the anabolic effect of    increase  sport performences .

Besides,  prolong oral intake of  salicylic  acid will cause the damages of mucosal layer of GI tract .One of the studies  conducted by Ryan et al (1995) showed that that aspirin ingestion may produce minor alterations in GI permeability in resting subjects and can produce marked increases in GI permeability during moderate treadmill running .When combined with moderate exercise, aspirin may interact in a synergistic manner to enhance GI permeability. The mechanisms by which aspirin markedly increases GI permeability during and following exercise are unknown because increases in GI permeability are thought to  increase in GI mucosal damage. They  speculated that aspirin-induced mucosal damage is either exaggerated or prolonged (impaired repair mechanisms) by the performance of exercise .This GI tract  permeability  can disturb the sport performances  because it may cause decreased ATP synthesis in mitochrondria, calcium leakage, reactive oxygen  reaction, altered Na+/K+, altered osmotic balance, dilatation  intracellular tight junction and also cause altered in ATP/ADP and ATP/AMP ratio that is  very important in  protecting  GI tract  from radical damage ( Lambert et al.,  2001)

NSAIDs are not believed to inhibit glycolysis because sufficient ATP could be derived anaerobically from glucose during NSAID-induced uncoupling of aerobic metabolism to maintain enterocyte integrity  (Bjarnason et al). They also suggest, when both substrates glucose and glutamine are present, citrate may inhibit phosphofructokinase and "funnel" glucose into the hexose monophosphate pathway, which would provide reducing equivalents for defense against oxygen radical damage. They alternately propose that these substrates may reverse the inhibitory action of indomethacin, allowing continued ATP production.

In conclusion, NSAIDs are widely used for treatment of athletic injuries. NSAIDs are very efficient against pain, early muscle recovery and injury in sport to allow faster return to the sport. But NSAIDs do not promote healing of bone fracture, tendon and ligament injuries. For sport performence purposes, NSAIDs are actually do not help at all but their side effect of prolong intake may worse the sport performances.

 

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