Volume de Treino no Deltoide: Estratégia Biomecânica ou Risco Articular?

Lateral raises with a flexed elbow are a commonly used strategy to increase deltoid training volume, but is this biomechanical manipulation always safe? In this video lesson, Professor Dr. João Moura analyzes the biomechanics of lateral raises, also understood as glenohumeral abduction, discussing how elbow flexion can reduce the moment arm and allow the student to continue performing repetitions even after deltoid fatigue. However, this strategy requires attention. When flexing the elbow, the weight moves away from the longitudinal axis of the humerus and can generate a rotational torque of internal rotation on the glenohumeral joint. This increases the need for isometric stabilization by the external rotators, especially the infraspinatus, teres minor, and posterior deltoid. 🧠 What you will learn in this lesson: How training volume can be increased in lateral raises Why flexing the elbow reduces the moment arm for the deltoid How weight position alters external torque on the shoulder Why elbow flexion can increase internal rotation torque What is the role of external rotators in glenohumeral stabilization When this strategy can be useful and when caution is required How to prepare the external rotators to better support this demand 📊 Biomechanical explanation In lateral raises with the elbow extended, the weight remains more aligned with the longitudinal axis of the humerus, generating less internal rotational torque. When the elbow is flexed, especially close to 90 degrees, the dumbbell shifts relative to the humeral axis. This displacement creates a rotational lever that tends to produce glenohumeral internal rotation. For the arm to remain stable during abduction, the external rotators need to act isometrically, resisting this tendency for internal rotation. 🎯 Practical Application for Exercise Prescription The elbow flexion strategy can be useful for increasing the training volume of the deltoid and supraspinatus, especially when the student can no longer maintain the exercise with the elbow extended. However, the Personal Trainer needs to observe whether the student has sufficient strength and control of the external rotators to sustain this position. Otherwise, the strategy can generate instability, loss of technical control, and increased stress on shoulder structures. Before using this variation frequently or with heavy loads, it may be necessary to include specific exercises to strengthen the rotator cuff, mainly for the infraspinatus and teres minor. ⏱️ Timestamps 00:00 — Introduction: Lateral Raise and Training Volume 00:15 — Coronal Plane, Scapular Plane, and Glenohumeral Abduction 00:48 — Deltoid and Supraspinatus in Lateral Raise 01:03 — How to Increase Volume in the Exercise 01:18 — Biomechanical Manipulation After Failure 01:43 — Moment Arm and Demand on the Deltoid 01:51 — Elbow Flexion to Reduce Resistive Torque 02:16 — Caution with the Strategy of Increasing Volume 02:37 — Relationship Between Weight and Longitudinal Axis of the Humerus 03:01 — Rotational Torque of Internal Rotation 03:25 — Isometric Action of External Rotators 03:40 — When the Strategy Can Create a Problem 04:20 — Infraspinatus, Teres Minor, and Posterior Deltoid 04:43 — Increasing Volume Without Losing Stability 05:18 — When technique is relevant 05:42 — How to avoid problems in prescription 05:59 — Specific training of external rotators 06:07 — Rotator cuff and glenohumeral control 06:15 — Strong muscles in internal rotation 06:57 — Practical application for the Personal Trainer 07:16 — Invitation for interaction and feedback #LateralRaise #Biomechanics #Deltoid #RotatorCuff #StrengthTraining #ShoulderTraining #ExternalRotators #PersonalTrainer #PhysicalEducation #Kinesiology #ExercisePrescription #ScientificWeightTraining 📲 Connect Follow me:   / joaomouratef     / treinoemfoco     / eksyapp      / @canaltreinoemfoco      / @eksyapp   Training and in-depth study for Personal Trainers - https://www.treinoemfoco.com.br/play/ Assessment and Prescription App - https://eksy.com.br/ MY E-BOOKS ON POSTURAL CORRECTION EXERCISES (Hotmart): How to Correct Postural Deviation of PROTRUDED SHOULDERS: https://joaomoura2009.hotmart.host/pa... How Correcting Valgus Knee Posture: https://joaomoura2009.hotmart.host/pa... How to Correct Lumbar Hyperlordosis Posture: https://joaomoura2009.hotmart.host/pa...