A tension spring for holding down a track body element, such as a rail foot of a rail, including a U-shaped main section which has a U-bend, a first leg arranged on one side of the U-bend and a second leg arranged on the other side of the U-bend, wherein a hook-shaped inwardly bent holding section which can be braced against a hold-down device is formed on the first leg and an end section bent towards or away from the holding section is formed on the second leg, wherein the U-bend forms a torsion section so that a hold-down force can be applied to the track body element via the bent end section.