Walking lunges, much like step ups, are an excellent exercise for building overall strength in the leg muscles, particularly if you prefer to jump off one leg. Their best use for jumping athletes is in developing general leg strength.
The further you step forward and the deeper you go into the lunge as you walk, the more you will recruit your hamstrings and glutes. If you take shorter steps you will place more emphasis on your quadriceps. For variety you could alternate between sets of longer strides and shorter ones to ensure you provide plenty of stimulation to both the posterior and the anterior chains.
walking lunges are a good leg strength builder, but if you want to really increase your vertical jump fast you need to check out the training methods in our book Game Changers: The Most Powerful Jump Training Techniques Known To Man.
These techniques provide gains far superior to regular jump training exercises. To find out more click on the banner below.