The aim of this study was to evaluate chronic adaptations in skeletal muscle strength and function in 12 chronic heart failure (CHF: all males, NYHA-class II, ICD implanted) patients (ITG: 67±5 yy, 75±14 kg, 174±6 cm) after a 16 week controlled and progressive resistance training program (1:30 hour, 3 times/week) on different muscle groups using 6 isotonic machines, based on 70% 1RM (previously calculated by Brzycki's formula and recalculated every fortnight). Before and after training, we calculated, for each subject: 1RM at all machines; total force TFI as the sum of all 1RMs, and the maximal rate of force development (RFD) in the leg press machine. For comparison we also tested 6 more CHF patients (ATG: 66 ±5 yy, 76±13 kg, 1715±10 cm) who followed an aerobic training for a similar period. The 1RMs in each muscle group were significantly improved by 53% in ITG and by 20% in ATG. TFI passed from 403 to 598 Kg (+48.8%, P<0.001) in ITG and from 412 to 495 Kg in ATG (+18.8%, P=0.02). The RDF showed a doubling (P=0.001) in ITG an increase by 31% (P=0.04) in ATG. Resistance training is a valid strategy to improve muscle force and function in CHF. Therefore, by this means, it may be possible to contrast muscle wasting in CHF and improve their quality of life.