What is there to a simple back step in the dance of Argentine tango?
A surprising amount.
There are three main parts to the back step of Argentine tango for the follower, and doing it all correctly takes some diligent practice. But the many rewards include poise, finesse, and most importantly an unbroken connection to your dance partner. An incorrect back step, on the other hand, can pull you and your partner slightly off balance, requiring an adjustment, and limiting the options for what could be lead next. So, let's break it down:
Feel the lead give the impetus for the step, which feels like pressure toward you and can be subtle. Respond to this by extending your unweighted leg behind you. Your goal is to make this an automatic response to the directional pressure of the lead, so that there is no delay. Extend your unweighted leg not just from the hip, but from higher up just under the rib cage. This pulls the hip itself back too, which must be out of the way so the lead can step in. While the leg is extending, keep the upper body projected forward toward your lead. There should be the sensation of a stretch in both directions: forward and upward in the upper body, backward and downward in the lower body.
A few examples of what extension looks like
One analogy is that your body, in tango, resembles a tree with the ground at your waist. Below your waist are the roots which stretch down toward the floor, and above the waist are the branches which stretch upward. The ability to simultaneously do both is one of the more challenging aspects of taking a good back step.
What, you don't see the resemblance?
When the lead's forward pressure builds enough to move you off your axis, transfer your weight onto your extended leg by pushing off gently from your weighted leg rather than simply landing on your extended leg. This infuses energy into the step and provides some extra length to the stride. Push off using just enough energy to get you solidly onto your other foot. If you use too much, you will send yourself past your new axis and be off balance. It takes practice for your body to understand how much energy to use here before it is consistently on the mark and becomes second nature. While executing this part of the step, be especially aware of projecting your upper body toward your lead while traveling backward.
Once you have weight on your other leg, ground yourself on your new axis. Being able to do this quickly is aided by pushing off with the correct amount of momentum when transferring weight. It also requires a sensitive lead who is not accidentally disturbing your balance. The goal is for the completion of every weight transfer to feel stable and balanced without any teetering or adjustment. Think of owning the space where you have arrived and feeling as if you could remain there poised indefinitely. Once your weight is over the new leg, disengage your other leg. This means that collecting your feet together feels more like gravity settling your new free leg underneath your new axis, rather than actively moving it there. This disengagement makes your unweighted leg free immediately for the lead to guide using momentum once you've changed weight. Performing adornments with the unweighted leg changes this sensation, but that's a different topic.
Starting from 1:45 this instructor demonstrates the back step slowed down.
Watch the opening 25 seconds of this performance by Luciano Brigante and Alejandra Orozco to see how each piece discussed here comes together into the action of the tango walk: