Background: Football is a popular sport with many subjects. Hamstring muscle strain injury is one of the most common injuries. This type of injury occurs at a high rate and has a high re-injury rate, which results in a loss of training and competition time. However, an efficient prevention and rehabilitation program could help to reduce the impact of injuries on football athletes.

Objectives: This study aimed to investigate and compare the effects of Nordic hamstring exercise in combination with electrical stimulation and in combination with the Federation International de Football Association 11+ program on football athletes with hamstring muscle strain.

Methods: Sixteen footballers from Kasetsart University’s Kamphaengsaen campus, aged 18 - 25 years old (mean age = 19.9 ± 1.5 years old), participated in the study. Through random sampling, the subjects were assigned to a group involving Nordic hamstring exercise combined with either electrical stimulation or FIFA 11+.

Results: The results showed that, after 6 weeks of training, both groups showed improvements in the strength of strained hamstring muscles (Nordic hamstring exercise with electrical stimulation was 9.8 ± 2.4 kg before training and 17.7 ± 2.0 kg on week 6; Nordic hamstring exercise with FIFA 11+ was 9.8 ± 2.8 kg before training and 15.8 ± 2.3 kg on week 6), but there was no significant difference between the 2 groups.

Conclusion: This study concluded that the training program used for either group could increase the strength of strained hamstring muscles.