Australian Cricket Junior Bowling Guidelines

Reviewed July 2023 by CA Head of Sports Science

The junior player pace bowling guidelines are based on available research and aim to reduce the risk of injury. Cricket Australia, and other research demonstrate that between 20%-33% junior (<19 years of age) pace bowlers develop a lower back (lumbar) bone stress injury (typically a stress fracture) each season. These injuries are hard to detect in the early stages and take between 4-12 months to recover and return to play. Prevention is the best approach.

The most vulnerable periods for bone stress injury (not just in the lower back) are just after puberty. The Cricket Australia research shows the 18 months after peak height velocity (maximum growth spurt period around puberty) present the highest risk of bone stress injury. This is likely to be because of changes in strength (and forces generated) post-puberty, increase in bowling load with transition to older age competitions and a relative weakness in the bone strength (bones grow long before they grow strong).

Recent Cricket Australia research* (published in 2021) highlight that there are 3 keys risk factors for lumbar bone stress injury in junior pace bowlers:
1. Age – the younger the bowler the greater the risk
2. Height – the taller the bowler the greater the risk
3. Bowling load – the more often they bowl in a week the greater the risk

Whilst we cannot change a player’s age and height, we can make changes to their bowling frequency (number of bowling sessions per week) to reduce the risk of sustaining a season ending injury.

By adjusting the number of bowling sessions per week, it allows time to reduce fatigue before the next bowling session and for bone (and other tissues such muscles, tendons etc..) to recover.

From time to time – every 6-12 weeks, a longer (5-10 day) break from bowling is recommended to allow for full recovery and for bone to adapt and become stronger.

Preparation (gradual build-up of bowling frequency and intensity) for the cricket season is also important to reduce fatigue and condition bone, muscles and tendons for the season ahead.

These guidelines apply to female and male players.

Key Messages

Under 15 and Under 17
1, 3, and 5
1 day off between bowling session, 3 days per week, 5 overs in a spell

Under 19
2, 4, and 6
Maximum 2 days bowling in a row, 4 days per week, 6 overs in a spell

Preparation

A gradual build up in bowling volume leading into a season or tournament so the player is physically ready to cope with the loads. This takes time (usually > 10 weeks) and some planning. In the 3-4 weeks leading into a season / tournament, bowlers should be close to expected match / weekly volumes and intensity.

Recovery

Recovery is essential to allow the body (particularly bones, muscles and tendons) to recover, adapt and be ready for the next session (training or match). Recovery between spells (to alleviate short-term fatigue), training & matches (to allow bone to adapt) and after prolonged high load periods, for example mid-season (to allow the physical and mental fatigue to resolve) are important injury prevention strategies and help maximise performance.

We recommend a week off bowling every 10-12 weeks, and a lighter bowling week every 4 weeks.

Specific Recommendations for Community Level

Age	Match Recommendations
u11	Two overs max each spell** 4 overs max per match day
u13	Four overs max each spell** 8 overs max per match day
u15	Five overs max each spell** 12 overs max per match day
u17	Six overs max each spell** 16 overs max per match day
u19	Six overs max each spell** 18 overs max per match day
	Rest between spells should be the same number of overs from the same end as the completed spell
Age	Pre-season Preparation Recommendations
u13	2 weeks gradual bowling prior to season/tournament
u15	4 weeks gradual bowling prior to season/tournament
u17	6 weeks gradual bowling prior to season/tournament
u19	8 weeks gradual bowling prior to season/tournament
Age	Training Recommendations
u13 – u17	At least 1 day off between bowling days* A maximum of 3 bowling days per week (match & training) A maximum of 5 overs in each bowling spell **
u19	No more than 2 bowling days in a row A maximum of 4 bowling days per week (match & training) A maximum of 6 overs in each bowling spell **

Age	Pre-season Preparation Recommendations
u13	2 weeks gradual bowling prior to season/tournament
u15	4 weeks gradual bowling prior to season/tournament
u17	6 weeks gradual bowling prior to season/tournament
u19	8 weeks gradual bowling prior to season/tournament

Recovery Guidelines

Allow one easy week (e.g. 1-2 bowling sessions) in every 4 weeks
Schedule a week off bowling after every 10-12 weeks of bowling to allow your body to recover

* It is recognized that some matches are scheduled on consecutive days both in tournaments & club cricket. In these instances, players may bowl on consecutive days but should strictly adhere to the other aspects of the recommended targets, namely, to not exceed bowling 3 days per week and 5 over spells.
** Minimum of 20 mins between spells

As an occasional occurrence, yes, particularly when matches are scheduled on consecutive days. If this occurs bowlers should adhere to other aspects of the guidelines, particularly on the number of bowling sessions per week and the number of overs in a spell (and break between them). But ideally, this age group should avoid back-to-back days to allow their body to adapt.
Common sense would suggest that there are very low loads that can be considered as low volume & managed appropriately. If the bowler feels okay, is well prepared & recovered well, they can bowl again soon afterwards. (e.g. next day)
Yes – fitness & strength training, batting, fielding are all examples of what is possible on non-bowling days.
Yes – bowling at or near maximum (match) intensity, generally results in high stress on the body so appropriate recovery periods are required. More lower intensity bowling can be factored into training plans and requires shorter recovery periods.
A fairly simple way to measure bowling intensity is for the player to rate the intensity out of 100%, with 100% being match intensity. Anything above 80% is considered high intensity bowling. Anything below 50% is low intensity bowling. In general, increased bowling intensity results in increased forces being generated through the bowling crease. This may, in some players, increase the risk of injury.
Like matches, if bowling at training is planned in multiple spells, then this will allow for some higher volume days. E.g. bowl 5 overs, have a break or do some other training & have another bowling spell. The break between spells allows your body to recover for the next spell.
Use the age group guidelines for frequency and recovery to create recovery periods.

A good start is to remove bowling session(s) at training that week and maximise the recovery between bowling days.

Sometimes, a young pace bowler needs to miss a game to make sure their body can cope.
Generally, the answer is yes. Girls do develop lumbar bone stress injuries and so the bowling guidelines apply to boys and girls.

Injury Risk Reduction

*What do we know? Research has shown an increased risk of injury associated with the following:**	Bowling guidelines to reduce risk
Low career and high 3-month bowling load	Gradual bowling preparation 8-10 weeks leading into season
<120 and >180 balls per week Players bowled less balls than the 2018-19 recommended targets (CA internal analysis)	Target balls 100-120 (U17) or 120-140 (U19) per week in month before season/tournament
<2 days between bowling sessions	At least 1 day off between bowling sessions (U17); max 2 days in a row (U19)
2.5 bowling sessions per week	Maximum 3 (U17) or 4 (U19) days per week
High load periods not followed by recovery period	1 easy bowling week every 4 weeks Plan recovery around high load periods (e.g., tournament)
<2 weeks off bowling during the season	1 week off bowling every 10-12 weeks
Younger age, taller and more frequent bowling	Gradual increase in bowling frequency and volume in each junior year to build resilience. Maximum 3 (U17) or 4 (U19) days per week

References

Orchard JW, Blanch P, Paoloni J, et al. Cricket fast bowling workload patterns as risk factors for tendon, muscle, bone and joint injuries. Br J Sports Med. 2015; 49(16):1064-1068. [elite adult male]
Dennis R, Farhart R, Goumas C, Orchard J. Bowling workload and the risk of injury in elite cricket fast bowlers. J Sci Med Sport. 2003; 6(3):359-367. [elite adult male]
Hulin BT, Gabbett TJ, Blanch P, Chapman P, Bailey D, Orchard JW. Spikes in acute workload are associated with increased injury risk in elite cricket fast bowlers. Br J Sports Med. 2014; 48(8):708-712. [elite adult male]
Kountouris A, Sims K, Beakley D, et al. MRI bone marrow oedema precedes lumbar bone stress injury diagnosis in junior elite cricket fast bowlers. Br J Sports Med. 2018; Published Online First: 13 November 2018. [pathway male]
Dennis RJ, Finch CF, Farhart PJ. Is bowling workload a risk factor for injury to Australian junior cricket fast bowlers? Br J Sports Med. 2005; 39(11):843-846. [club/district junior male]
Sims K, Saw R, Saw A, Kountouris A, Orchard J. Multiple risk factors associated with lumbar bone stress injury in youth cricket fast bowlers. Sport & Exercise Science New Zealand, Vol. 5, Issue 2, 92-100, 2021