Culturally appropriate, evidence-based, personalized dietary advice to improve the nutritional status of track and field athletes: a randomized controlled trial

Background: Optimal nutrition is vital for recovery, performance, and well-being of athletes. However, Sri Lankan track and field athletes often fall short of dietary recommendations due to the lack of personalized nutrition guidance. This study evaluated the effectiveness of culturally appropriate, evidence-based, personalized dietary advice on the nutritional status of these athletes. Methods: This 16-week parallel-group randomized controlled trial included 30 national-level track and field athletes (15 in the intervention group [IG], 15 in the control group [CG]). The IG received personalized dietary prescriptions based on detailed nutritional assessments, while the CG received no advice. Outcomes included dietary intake, assessed via seven-day food diaries, and biochemical parameters measured using standard techniques. Results: Twenty-seven athletes (IG: 13, CG: 14) completed the study. The IG showed significant increases in energy intake (Pre: 2766.0 ± 494.0 kcal, Post: 3972.9 ± 934.4 kcal, Change: +1206.9 kcal; p = 0.007) compared to the CG (Pre: 2733.7 ± 635.5 kcal, Post: 2676.5 ± 319.2 kcal, Change: -57.2 kcal; p = 0.739; p for IG vs. CG = 0.004). Protein intake also improved significantly in the IG (Pre: 95.56 ± 30.2 g, Post: 116.81 ± 41.8 g, Change: +21.25 g; p = 0.003) versus the CG (Pre: 94.54 ± 32.8 g, Post: 84.24 ± 16.4 g, Change: -10.30 g; p = 0.162; p for IG vs. CG = 0.001). The IG exhibited improved vitamin and mineral intakes, and serum vitamin D levels in the IG increased significantly (Pre: 30.55 ± 10.2 ng/ml, Post: 42.02 ± 9.6 ng/ml; Change: +11.47 ± 0.6 ng/ml; p < 0.001), while the CG showed no change. Serum ferritin levels also increased in the IG (Pre: 44.76 ± 29.3 ng/ml, Post: 51.54 ± 28.4 ng/ml, Change: +6.78 ± 0.9 ng/ml; p < 0.001), along with positive changes in haemoglobin and other haematological parameters. Conclusions: A culturally appropriate, personalized dietary prescription significantly improved the nutritional status among Sri Lankan track and field athletes.