3.3.1. Hypothesis 1
Hypothesis 1 proposed that nitrate supplementation would have a significant positive effect on covered distance in the Cooper performance test compared to placebo if the baseline dietary nitrate intake was low (<300 mg nitrates) in both the placebo and intervention groups. In 13 participants, the baseline nitrate intake was below 300 mg in both the placebo and the intervention groups, with two players exceeding these baseline values and being omitted from Hypothesis 1. The football players in the intervention group had an average covered distance in the Cooper performance test of 2.98 km, with a standard deviation of 0.28 km, minimum of 2.48 km, and a maximum of 3.52 km. The average distance covered by the placebo group was 2.84 km, with a standard deviation of 0.23 km, minimum of 2.4 km, and a maximum of 3.5 km (