Overall, 13.4% of professional Ugandan athletes in our study used nutritional supplements. Most of these athletes played either basketball or rugby. Athletes who used supplements mostly consumed carbohydrate supplements, energy drinks, vitamin and mineral supplements, protein supplements, and fish oils. These supplements were consumed 3 times per week on average, and most supplements were acquired from a dietician, a local retail store, a pharmacy, or from fellow teammates. Most athletes consumed supplements to improve performance, boost immunity, prevent deficiencies, improve physical appearance, and decrease stress. Regarding perceptions of nutritional supplement use, athletes who used supplements believed that the supplements made them healthier, were safe to use, helped them cope with pain, improved their concentration, and contained doping agents. Most athletes who lacked knowledge about supplements had never used them before.

The prevalence of supplement use among professional athletes in the current study is low compared to what was previously reported ([5, 8, 13, 18]; [6, 14]). One explanation for this finding could be that the assessment tools for supplement use adopted by the current study may have underestimated the true prevalence of supplement use in an athlete population. The reported prevalence of supplement use in the current study compared to the prevalence from a similar study involving rugby players under the age of 16 in South Africa [14] is low even when corrected for geographic location and population characteristics. Because of the paucity of data on supplement use in developing countries, many parts of the current study tool were adapted from similar studies performed in developed and middle-income countries. As such, less emphasis was placed on the herbal varieties of nutritional supplements, which are indigenous and popular among the local people in Uganda. This may have resulted in under-reporting of supplement use by the athletes. However, it is still possible that the reported prevalence is a true representation, since no dietary evaluation was undertaken to ascertain that the athletes were nutritionally deficient, and thus required nutrient supplementation.

Socio-economic status is a known determinant of supplement use amongst athletes, with athletes of higher education status, or those having higher level paying jobs reported to use supplements more than their counterparts of lower education status, or those with lower paying jobs [3, 4, 25, 26]. These findings partly conform with findings from our study, where nutritional supplement use was significantly higher in athletes with a tertiary education. However, despite its predictive potential from earlier studies [3, 4, 25, 26], athleteís occupation in the current study had no significant association with nutritional supplement use. Small numbers of supplement users in the occupational sub-groups in the current study possibly confounded this association.

The prevalence of supplement use by athletes of both genders in the current study was similar. This finding corroborates previous observations [3, 4], although it is not consistently reported in the literature [6, 13]. Unlike in previous research findings [15], the athletesí age had no correlation with supplement use in the present study. However, the duration of time spent playing the sport was significantly correlated with nutritional supplement use; supplement use was more prevalent among athletes who had competed in the sport for 5-10 years than in their counterparts who had competed for shorter (10 yrs). It is proposed that younger athletes (who may share similar characteristics with athletes who have competed for