A great source for Yoga Postures by Mark Giubarelli.
Translation: Warrior 1 Pose
Raise the upper body stretching the arms above the head. The hands can be in prayer position, interlocked or shoulder width apart. The fingers can be closed or open. (One creates a direct force and the other is a flared force.)
The chest faces forward. The heels are in line but you can also perform this pose with a little width between the heels. This will slightly change the alignment of the hips and can improve the alignment.
The navel area will naturally stick out. To engage lower core abdominal muscles pull the navel up and back. This will reduce pressure on the lower back.
Aligning the shoulders horizontally is desired. There are many ways to do this. Shown opposite is a method of lifting them. Sometimes this is not done because of blood flow interference or nerve impingement. It is quite nice to have all the muscles, skin and cells around the arms and shoulders moving in an upwards direction. The energy forces of the pose feel better.
Tips for Warrior 1 Pose
It is very hard to get the back foot flat on the mat if the legs are too wide apart. It also makes it harder to face forward correctly with the chest. Therefore adjust the legs to a distance apart that allows both the back foot to be on the mat and the chest to be forward.
Benefits of Warrior 1 Pose
Both legs are strengthened in this pose. It can also help the knee muscles strengthen.
This pose is quite hard on the lower back. It will be hard to perform on one side if a disc is slightly inflamed or bulging. This can be avoided by reducing the distance of the stance. Taking the legs closer together will greatly reduce the amount of pressure in the lower back.
Vinyasa Yoga Sequencing for Warrior 1 Pose
Vinyasa Yoga postures to transition from and to:
Virabhadrasana 2 Yoga Postures Tadasana Trikonasana Parivrtta Trikonasana Virabhadrasana 1 Urdhva Virabhadrasana 2 Parsvakonasana Revolved Lunge Utkatasana Uttanasana Vrksasana Virabhadrasana 3 Reverse Half Moon Pose Downward Dog Pose, Eka Pada Adho Muka Svanasana Parivrtta Parighasana Parsvottanasana
From the Downward Dog Pose step one leg forward between the hands. Externally rotate the back leg until the heel touches the mat.
Yoga Teacher Tips
It can be hard on the back if injury is present and this yoga position is entered too fast or too deep. It can also be a vary therapeutic yoga position when done mildly.