The aim of the study is to assess the impact of 4 weeks of eccentric Nordic Hamstring Exercise training on changes in the hamstring muscle group, as well as to analyze parameters such as maximum muscle strength of the knee flexors, RFD (rate of force development) and static balance, dynamics for the dominant leg.

Research procedure: Nordic Hamstring Exercise training covers a period of 4 weeks, during which the volunteer exercises 3 times a week for 3 sets, each set consisting of 3 repetitions of NHE. Before starting eccentric exercises, you will warm up for 15 minutes. After each series, there will be a 2-minute passive break, during which the subject will rest. In the first week, the subject will exercise under the supervision of the instructor, in the next three weeks the subject will exercise at home after prior instruction.

Inclusion Criteria:

• healthy people aged 19-26,
• no injuries,
• athletes, people practicing sports as amateurs

Exclusion Criteria:

• during the period of greatest training load related to the discipline,
• overload changes in the joints: knee, hip and lumbar-sacral,
• pain,
• muscle fatigue, overtraining,
• in strength sports a few weeks before the start,
• inflammation of the osteoarticular and ligamentous elements of the lower limbs,
• previous injuries, surgical procedures within 6 months before the intervention

The study will involve students of the Academy of Physical Education and Sport in Gdańsk, aged 19-26 who practice amateur football.