We prospectively studied the effect of heavy-load eccentric
calf muscle training in 15 recreational athletes
(12 men and 3 women; mean age, 44.3 ! 7.0 years)
who had the diagnosis of chronic Achilles tendinosis
(degenerative changes) with a long duration of symptoms
despite conventional nonsurgical treatment. Calf
muscle strength and the amount of pain during activity
(recorded on a visual analog scale) were measured
before onset of training and after 12 weeks of eccentric
training. At week 0, all patients had Achilles tendon
pain not allowing running activity, and there was significantly
lower eccentric and concentric calf muscle
strength on the injured compared with the noninjured
side. After the 12-week training period, all 15 patients
were back at their preinjury levels with full running
activity. There was a significant decrease in pain during
activity, and the calf muscle strength on the injured
side had increased significantly and did not differ significantly
from that of the noninjured side. A comparison
group of 15 recreational athletes with the same
diagnosis and a long duration of symptoms had been
treated conventionally, i.e., rest, nonsteroidal antiinflammatory
drugs, changes of shoes or orthoses, physical
therapy, and in all cases also with ordinary training
programs. In no case was the conventional treatment
successful, and all patients were ultimately treated
surgically. Our treatment model with heavy-load eccentric
calf muscle training has a very good short-term
effect on athletes in their early forties.