The present invention relates to a method of creating a biomarker profile, the method comprising the steps of: obtaining a sample of biofluid from a subject, wherein the sample is stored on a sample collection apparatus; removing the sample from the sample collection apparatus; extracting nucleic acids from the sample; sequencing the extracted nucleic acids to generate sequence data; and analyzing the sequence data using a two-step analytical methodology to create the biomarker profile. The present invention athletic performance in a subject.