The muscles of the legs are divided into the following groups: the muscles of the thigh and the muscles of the shins, the joints of the ankle, knee, and hip participate in the work of the muscles. When performing certain exercises, the connection between the spine and the pelvis also participates.
• Thigh muscles flexors: Iliopsoas, Rectus Femoris (group of quadriceps).
• Thigh muscle extensors: Hammstrings (hamstrings biceps triceps) consists of: Bicepce Femoris, Semitendinosis, Semimembranosis, Gluteus Maximus (the gluteus maximus muscle).
• Muscles of the extensor of the knee: Quadriceps (quadriceps femoris) consists of: Rectus Femoris, Vastus Medialis, Vastus Lateralis, Vastus Intermedius.
• Muscle flexors of the knee: Hammstrings, Gastrocnemius (gastrocnemius muscle).
• Muscles of the lower leg: Gastrocnemius, Soleus raise the heels (Plantar Flexion), Tibialis Anterior lifts the socks (Dorsi Flexion) with the participation of the foot.
• Hip reduction muscles: Hip Adductors – Adductor Brevis, Adductor Longus, Adductor Magnus, Gracilis, Pectineous, and Sartorius muscle.
• Hip abductor muscles: Hip Abductors – Gluteus Medium, Gluteus Minimum.
Exercises on leg muscles can be both multiarticular and single-joint.
1. Squat. Squat with a free barbell. Hip Isolation Exercises
This exercise mainly affects and strengthens Quadriceps (quadriceps femoris). However, when considering the exercise in the context of various joints, we get a fairly energy-intensive work, which includes many muscle groups. Let’s take a look at the example below. I draw the attention of trainers, instructors and athletes to the important information that I have provided. Types of levers are presented in the biomechanics section.
2. Squat using Smith Machine. Hip Isolation Exercises on a Smith machine
Position: the back is straight, the legs are shoulder width apart, the toes are parallel or slightly unfolded outwards. The execution of this hip isolation exercises are very similar to the exercise with a free bar, but in this case we significantly reduce the burden on the muscles of the back rectifiers. The load on the knee joint is reduced. The muscle groups shown in the table above work. Hip Isolation Exercises Plane: Sagittal.
Common mistakes during the exercise:
• The knee runs forward, that is, crosses the line of the toes that is caused by the motionless pelvis.
• The back leans too far forward. There can be a movement of the center of gravity of the athlete, which is quite dangerous for him and others.
• Lifting the heels, which is often found with a short gastrocnemius muscle or hamstrings. In this case, it is impossible to achieve the correct execution of the exercise.