ExercisesSport-Specific Drills
One-Arm Block Jump: A Complete Guide
Quick Intro
One-Arm Block Jump is a Sport-Specific Drills exercise performed standing, jumping vertically and reaching with a single arm to block or deflect a target, replicating the single-arm reach used when blocking near the sideline. Keeping the takeoff square while the reach is one-sided preserves both height and control.
Equipment Needed
No equipment is required. A net, a wall mark or any fixed overhead target gives the reaching hand something to aim for.
Why It Matters
Jumping for height while reaching with one arm and staying upright in the air asks for balance, coordination and power together. The largest glute muscle (gluteus maximus) drives the explosive hip extension into the jump, a front thigh muscle that crosses both the hip and knee (quadriceps, rectus femoris) drives the knee extension through takeoff and a calf muscle (gastrocnemius) pushes off through the ankle at takeoff. The front of the shoulder cap (deltoid, anterior) drives the reaching arm up and overhead, and the side of the shoulder cap (deltoid, lateral) assists the arm through the single-arm reach. The muscles along the sides of the abdomen (obliques) control the trunk against the asymmetrical reach, and a muscle across the upper back and neck (trapezius) supports the shoulder blade through the reach.
When to Do It
One-Arm Block Jump fits well as the finishing step in a blocking progression, done once the two-arm version is already solid. A couple of focused sessions a week is enough to build single-arm reach height without overloading the shoulder.
Anyone with a current shoulder or ankle issue should get individual guidance before loading up a full set of maximal single-arm jumps, since the one-sided reach loads the shoulder and the landing loads the ankle.
Getting Ready
A few lighter jumps with the single-arm reach check the takeoff squareness this drill depends on. A couple of two-arm jumps preview the leg mechanics before the single-arm version is attempted.
Step-by-Step Instructions
- Start in an athletic stance. Face the target with the feet shoulder-width apart, the knees slightly bent and both hands in front of the chest.
- Load the countermovement. Dip quickly at the knees and hips to prepare for the jump.
- Drive up and reach with one arm. Extend the hips and legs while the single arm reaches overhead.
- Land softly and square. Come down on both feet with bent knees, centered under the body, and reset before the next rep.
How Many, How Often
One-Arm Block Jump is dosed by reps per side, with each full jump counting as one.
| Level | Where you’re at | What to do |
|---|---|---|
| Beginner | New to keeping the takeoff square with an asymmetrical reach | 3 sets of 4 to 5 reps per side |
| Intermediate | The takeoff stays square through the single-arm reach | 3 to 4 sets of 5 to 6 reps per side |
| Advanced | Producing maximal height with the reach fully controlled | 4 sets of 6 reps per side |
Keeping the takeoff square matters more here than how high the reach extends, since a jump that tilts sideways loses both height and control.
Modifications and Variations
As an easier version, Block Jump — Vertical Reach uses a two-arm reach, which keeps the body even in the air. Jump and Touch Target sits one step below that, with no approach, and is the way to scale it down further.
Common Mistakes to Avoid
Letting the takeoff tilt toward the reaching arm. Allowing the jump to lean sideways to assist the reach reduces the height the legs can produce. The takeoff stays square and centered.
Reaching with a bent arm. Shrugging the shoulder up without fully extending the arm wastes some of the available reach height. The arm extends completely at the top.
Landing off-balance. Coming down still leaning toward the reaching side places unnecessary stress on the landing leg. The landing resets square under the body.
After Your Set
An overhead shoulder stretch eases the reaching arm once the jumps are done. A standing quadriceps stretch loosens the front of the legs as well. Alternating the reaching arm from set to set keeps both shoulders evenly trained.
Going Deeper
A takeoff that stays square lets the single-arm reach add height without tilting the jump sideways. The hips tend to drift toward the reaching arm as fatigue sets in. Dropping back to the two-arm version for a stretch of practice and rebuilding the square takeoff from there fixes this faster than repeating single-arm jumps that tilt off balance.
A beginner typically needs the first several sessions to keep the takeoff square, then spends the following couple of weeks building toward maximal single-arm reach height.
How to Know You’re Improving
- A takeoff that stays square under a one-sided reach
- An arm that fully extends at the top of each reach
- A landing that resets centered under the body on each rep
- A reach height that climbs while the takeoff stays controlled
A square takeoff matters more than how high the arm reaches.
Muscles Worked
- Gluteus Maximus (the largest glute muscle, producing the jump height a single reaching arm cannot add)
- Rectus Femoris (a front thigh muscle that crosses both the hip and knee, extending the knee at takeoff for a single-arm block)
- Gastrocnemius (a calf muscle, driving the ankle extension underneath a single-arm reach)
- Anterior Deltoid (the front of the shoulder cap, driving one arm up to its full height)
- Lateral Deltoid (the side of the shoulder cap, assisting the arm through the single-arm reach)
- Obliques (the muscles along the sides of the abdomen, controlling the trunk against the asymmetrical reach)
- Trapezius (a muscle across the upper back and neck, supporting the shoulder blade through the reach)
FAQ
Why does takeoff squareness matter more than reach height? A jump that tilts to help the reach produces less height overall, while a square takeoff lets the legs contribute their full power with only one arm reaching.
Is there a two-arm version of this drill? Yes, Block Jump — Vertical Reach uses a two-arm reach, worth having solid before the single-arm reach is added.
Is some leg or shoulder fatigue after this drill normal? Yes, the legs and reaching shoulder feel worked after a full session of maximal jumps. Pain that keeps building in the shoulder or a landing ankle deserves a doctor’s attention.
Does it matter which arm does the reaching? Both sides are worth training, since a block near the sideline can call for either arm depending on where the target is.
How often should the one-arm block jump be trained? A couple of focused sessions a week is enough.
Related to Block Jump — Vertical Reach as the easier version with a two-arm reach.