The study objective is to determine the possibility of identifying the state of strength abilities development in boys aged 12-14, using the methodology of multidimensional statistics.
 Materials and methods. The study involved boys: 12 (n =35), 13 (n = 36), 14 (n = 36) years old. The study used the following methods: analysis and collation of scientific and methodological literature, general scientific methods of theoretical level, such as analogy, analysis, synthesis, abstraction, induction, as well as general scientific methods of empirical level: observation, testing, experiment. The testing program included well-known tests.
 Results. In identifying the state of motor abilities development in boys aged 12-14, the most important results were obtained in tests: 10 “Squats Test (two legs), quantity of times” (0.519), 9 “Trunk Lift Test, quantity of times” (0.497), 21 “Flamingo Balance Test - single leg balance test” (-0.496), 1 “Pull-Up / Chin Up Test (low crossbar), quantity of times” (0.428), 19 “Hand Tapping Test, sec.” (-0.427), 20 “Seated Forward Bend, cm” (-0.412), 5 “The subject lies in prone position, arms bent at the elbow 90 degrees - hold position in seconds” (0.408). These tests characterize the comprehensive development of motor abilities in boys aged 12-14. 
 In identifying the state of motor abilities development in boys aged 13-14, the most important results were obtained in tests: 8 “Decline Reverse Crunch on Bench, quantity of times” (-0.989), 11 “Single Leg Squat (SLS) Test - right leg, quantity of times” (0.965), 1 “Pull-Up / Chin Up Test (low crossbar), quantity of times” (0.676), №13 “Single Leg Squat (Pistol) - right leg” (0.682), 17 “Eurofit Sit Up Test (for 30 sec.), quantity of times” (0.454). These tests characterize the development level of relative and static leg strength, strength endurance of abdominal muscles, and dynamic strength of shoulder muscles.
 Conclusions. A discriminant analysis made it possible to determine informative indicators for comprehensive control of motor abilities development in boys aged 12-14; to answer the question as to how significantly the states of motor abilities development in boys aged 12, 13 and 14 differ; what motor tests most substantially influence the differentiation of classes; what class the object belongs to based on the values of discriminant variables.
 To identify the level of motor abilities development in boys aged 12-14 years, it is necessary to focus on the indicators of relative strength and strength endurance; in boys aged 13 and 14 years – on the indicators of strength endurance of abdominal muscles and endurance of leg muscles.
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