There isn't a separate income level for sports massage therapists.
ABMP reports that the average income is about $32,000 per year:
From their website: Average massage-related income for massage therapists in 2005 was $18,950, with a median income of $14,500 (2005 ABMP Member Survey). An American Massage Therapy Association (AMTA) fact sheet erroneously asserts that massage therapists earn an annual income “comparable to other healthcare support workers,” on the basis of misleading numbers supplied by the U.S. Department of Labor, Bureau of Labor Statistics (BLS), exacerbated by an AMTA further assumption.
# Total earnings by massage therapists, including their earnings from other employment, were $32,506 (2005 ABMP Member Survey).
# First-year practice average income was $9,589, reflecting the challenges of establishing a professional-service practice (2005 ABMP Member Survey).