Learn the roll shot in volleyball: topspin from the wrist, the same arm swing as a spike, aimed behind the block. With milestones and typical mistakes.
What is a roll shot? The honest answer: An attack with a full arm swing in which you do not hit the ball hard but "roll" over it with topspin. It flies slowly, rises over the block and drops quickly behind it. The Swiss Mobilesport material describes it as a lightly hit, placed topspin shot usually played over the block [2].
There is a surprise in the numbers. In a lab study with 14 collegiate women, forces, torques and angular velocities at shoulder and elbow were lowest for the roll shot, even below the float serve. For the hard hits they were clearly higher [1]. So compared with a full hit, the roll shot relieves the shoulder. That does not make it a guarantee against problems, but it is an honest alternative when you want to save repetitions.
The roll shot lives from the wrist. The association material lists as standard errors in attacking that wrist action is missing or minimal and that the hitting arm is bent rather than straight at contact [7]. That is exactly what you practise here: from a short distance (2 to 3 metres) hit a bounce ball against a wall with a straight arm and active wrist [7]. Milestone: 10 bounces in a row in which the ball "rolls off" forwards.
Toss the ball to yourself and place it over the net with topspin, deep into a corner. The open hand rolls over the top of the ball. That is a practical description. What matters is that the ball rebounds cleanly and does not stay in the hand, otherwise it is a fault [4]. Milestone: 7 of 10 balls land in a 2-metre target circle behind the attack line.
As with the tip: everything up to contact looks like a hit. Approach, high elbow, arm pull. Then you leave out the hard hit and roll the ball. The association material asks you to meet the ball at the highest point with a straight arm [7]. Milestone: 6 of 10 roll shots land in the target area without anyone reading the direction at take-off.
A roll shot should fly high enough to clear the block and drop shortly behind it. Too flat: the block catches it. Too high: the defence has time. Dose with the wrist, not with the shoulder. Milestone: out of 10 attempts you can play 5 high and short and 5 flat and long, as called.
The roll shot pays off when the block is high or the opponent waits deep. As individual tactics the tactics material lists "tip or spike" [6], and against the tip it advises defenders to move their position forward [6]. So mix. Milestone: in a 3-on-3 you vary hit, tip and roll shot without the defence recognising a rule.
The roll shot loads the shoulder less than a full hit, but not zero. In the study, shoulder abduction was about 130 degrees in all techniques tested (the arm is well above shoulder height), clearly more than reported for tennis serves or baseball pitches [1]. A survey of 175 high school players found that 40 percent had already experienced shoulder pain without injury [8]. That is self-report and may be misremembered. If your shoulder hurts, reduce repetitions and have it checked [1]. This guide explains and motivates, it does not replace supervised training.
Use the roll shot deliberately when you want to save full hits and thus shoulder repetitions. The lab study confirms that this shot puts clearly less load on shoulder and elbow than a full hit [1]. On sand there is something else: players adapt their movement to the yielding surface, and on sand the movements slowed especially in the transition between knee flexion and extension [5]. Rolling rather than hammering suits that anyway, an inference, not a study finding.
In a tip you place the ball briefly over the block with your fingertips. A roll shot is a topspin hit with the hand that flies slowly over the block and drops behind it [2]. Both must be played cleanly [4].
In a lab study, forces and torques at shoulder and elbow were lowest in the roll shot [1]. That is a measurement on 14 players, not a promise of protection.
When the block is high or the defence waits deep. Alternate, because against the tip the defence moves forward [6].
With an active wrist over the top of the ball, practised from a short distance at the wall [7].
Cut Shot: Attacking Short and Diagonal When the Line Is Closed