As in baseball, the search for the latest marking gimmick or training “trick,” is also apparently becoming prevalent with youth softball development. The promise of, and fear of not having, pitching velocity is a driving factor for many kids and parents. Unfortunately, in what’s becoming more and more of frequent method regardless of skill or physical ability; overload and underload softballs are being used as the answer to velocity development with middle school and young high school girls.
What does the research say about the effectiveness, injury risk/increased stress or even standard protocol for weighted softball use in young females or any age females for that matter? Very little in fact.
In fact, I could only find one study, from 1992, that used college age, novice softball players and found no increase in throwing velocity, wrist strength or handgrip strength compared to control group. Hardly the supportive research needed to claim that weighted softball use is safe.
It is true that weighted implement use has been around for a very long time and has been shown to improve performance through overload/underload shot put use by track and field throwers as well as overload/underload baseball use by baseball players.
It’s also true that there are some people pushing the envelope with aggressive weighted baseball throwing programs in terms of volume, intensity and types of throws being used, beyond what research has shown to be safe and effective. Likewise, there is some limited research starting to be made public that suggests misapplication or too high of intensity of overload/underload baseball use may result in injury or in structural adaptations that may increase injury risk. There are some positive benefits, but also risks associated with overload/underload baseball use.
I wrote a blog post several months ago detailing the research, benefits and risks. Check it out here. weighted baseball research
To directly extrapolate research pertaining to overload/underload baseball use as a means to justify overload/underload softball use safe and effective is misguided. Without a doubt, research from the sport of baseball can serve as a beginning guideline to research that needs to be done in the sport of softball. However, baseball and softball are two very different populations and skills (male vs female, overhand pitching vs underhand windmill pitching, mound vs flat circle). Therefore, one can’t assume the same exact results with softball players. Likewise I have seen some professional and high level D1 softball players held up as examples of the benefits (and no risk) of overload/underload softball use. Again, not even close to a fair comparison. A pro softball pitcher who has probably been through a very good D1 strength and conditioning program for 4 years, not to mention has a very high skill level is not exactly the same as an 8th grade female who can’t do a push up.
What does research say about the forces experienced during windmill pitching? For starters, a study by Dr. Glenn Fleisig, Dr. James Andrews and others found peak compressive forces at the shoulder and elbow reached 70-98% of bodyweight. Shoulder extension and abduction torques reached 9-10% of bodyweight x height. Check out the full study Biomechanis of Windmill Softball Pitching
That’s quite a bit of stress, especially for young, untrained softball pitchers, to handle.
A study by Guido et al. found peak vertical ground reaction forces averaged 139% of bodyweight. Peak anterior force averaged 24% of bodweight. Finally, medially directed ground reaction force averaged 42% of bodyweight. They also noted that pitchers in this study who had longer strides, reached stride foot contact later in the delivery and had greater pitching velocity. Here is the study. Lower-extremity ground reaction forces in youth softball pitchers
What does all that mean? The inability to control that force places more stress on the lower body, potential increasing load on the knees, hips and lower back or in simple terms: places more load on joints and ligaments to create stability instead of muscles. It also results in an energy link in terms of transferring force to the upper body. Conversely, the ability to control that force results in energy being transferred to the upper body and arm during pitching. In short, effective use of the lower body during softball pitching is a big key to reducing pitching stress and increasing pitching velocity.
We know windmill softball pitching places a significant amount of stress on the shoulder and elbow. We also know the lower body experiences significant forces during windmill softball pitching. Finally, we also know the ability to create ground reaction force and control ground reaction force with the lower body results in higher pitching velocity and a better distribution of force (stress). How can young, female softball players create more effective use of their lower body? Get stronger, develop proper movement patterns, such as a hip hinge, develop real, (not just the ability to balance on 1 leg) single leg strength, and become more athletic.
From my own experience working with youth female athletes and softball players and I would venture other strength and conditioning coaches are also able to verify: the number of young or even high school aged females softball players, prior to any physical training who can’t properly do 1 push up, 1 chin up, or squat, deadlift or lunge their bodyweight greatly exceeds those that can reach those levels. Yet many of those same young softball players have been playing and receiving pitching lessons long before they have even thought about physical training.
Telling young female softball pitchers that if their velo isn’t X by age X and giving them overload/underload softballs to use to increase their pitching velocity, is, in my opinion, a poor development process and potentially places those girls at a greater injury risk. The obvious low hanging fruit is to encourage them to get on a physical and athletic development plan. Very low risk, very high reward. It’s pretty likely their velocity is low because they have never trained, move poorly and have poor relative strength to bodyweight. How will using an aggressive overload/underload softball throwing program fix that? All those programs will be doing is placing more emphasis on the upper body (arm) to generate velocity and if they do increase velocity; then adding more force to a athlete ill equipped to handle it. How is that risk worth the reward for a young female softball pitcher?
No doubt, the pressure on young female softball pitchers to throw hard is real and certainly velocity is a factor when it comes to being recruited by D1 schools. However, we should still think long term development with these girls and set them up for both long term performance and health. The majority of middle school and early high school female softball pitchers are no where close to the level of physical development they should/need to be at if they want to play and be successful at the D1 level. Long term development means proper physical development, giving them a break from pitching 8 months out of there year and teaching them how to use their improved physical ability to enhance their mechanics.
Weighted softball use may be one small part of overall pitching development if they are used correctly (how do we even know what that means right now?) gradually implemented and used with females who are physically mature and have the ability and skill to benefit from them. Right now, they are being used with anyone and everyone as a one size fits all program regardless of skill, physical ability or training history. In my opinion, that is the incorrect use and implementation of overload/underload softballs and is putting short term gains ahead of long term development.