Aquatic Plyometric Training: Safety and Effectiveness (Part 1 of 2)

Plyometric jumping builds power, and done badly it builds soreness and injuries too. The pool offers a way to get the first without as much of the second.

Part 1 covers why water works and why depth matters.

Want to go deeper? Explore the 12 Ways to Progress Any Aquatic Exercise course →

Plyometric training, widely utilized to enhance muscle power, is a series of exercises designed to achieve rapid muscle elongation followed by quick contraction. This type of conditioning has been well-documented in the medical literature to enhance dynamic muscle performances, such as vertical jump height,¹ agility,² isometric torque in knee extensors,³ and balance.⁴

However, plyometric training may cause inadvertent muscle soreness and injury when these high intensity exercises are not performed correctly.⁵ Overexertion and the lack of prior experience with plyometric training are common causes that enhance the chances of soreness/injury.

Aquatic plyometric training offers a solution to gaining muscle strength while reducing the risks associated with land-based plyometric exercises. The buoyancy of water lowers weight bearing on limbs leading to reduction in exercise-related physical stress. This article describes the advantages of performing aquatic plyometric training, different water conditions for these exercises and different training protocols that may be followed.

Water a Preferred Environment

In general, aquatic exercises are gaining popularity in recent times because the water environment provides numerous physiological benefits. The most obvious advantages of water-based exercises are reduced muscle/tendon/joint stress, greater involvement of muscles to help maintain balance in water, as well as greater muscle building power while working with the water resistance. In addition, certain circulatory and cardio-respiratory benefits⁶ are also observed with water exercises.

The reduced joint impact of aquatic training may be particularly beneficial for the elderly population. A study conducted in elderly women undergoing aquatic training for 24-weeks, showed improved isometric torques for knee extensors and knee flexors, grip strength and functional mobility (timed-up-and-go test).⁷

Similarly, patients with coronary artery disease have shown improvement in both exercise tolerance and muscular strength upon 4-months of water-based exercise program.⁸ In this study, the subjects also reported a favorable change in total cholesterol, triglycerides and body composition upon completion of the study.

Finally, aquatic training provides a safe environment for strength recovery during rehabilitation. Individuals with certain conditions that necessitate reduced joint stress may benefit from aquatic based training. In fact, the Osteoarthritis Research Society (OARSI), the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR) support the use of aquatic exercise to control the symptoms of knee osteoarthritis.⁹ Article on Plyometrics 2

How effective is aquatic plyometrics?

Medical research has demonstrated that aquatic plyometric training is as effective as land-based methods in enhancing muscle performance. A study by Stemm et al¹⁰ sought to compare jump performance improvement following aquatic-based versus land-based plyometrics. College-age men were enrolled in the study and randomly divided into three groups—the aquatic training group, the land-based training group and the no-training group. The aquatic training group performed a series of jumping exercises (squat jumps, side hops and knee-tuck jumps) in knee-level water, while the land-based group performed identical exercises on land. Following a 6-week training period (2 sessions/week) it was observed that the vertical jump heights of both aquatic training group and land training group were significantly higher than that of the no-training group. Aquatic plyometric training also helps prevent muscle soreness compared with that observed in land-based training, as indicated by the levels of CPK, an inflammatory enzyme.^11,12 In their study, Shiran et al¹¹ used male wrestlers in a 5-week training period (aquatic vs. land) to demonstrate comparable increases in leg muscle strength.

Another study has compared aquatic vs. land plyometric training in young basketball players.¹³ This study concluded that aquatic plyometric training is as effective as land plyometric training in improving sprint performance, which requires explosive muscle power. However, the authors point out that improvement in dynamic balance was greater in the land training group compared with that of the aquatic training group. A possible explanation is that water provides a safer environment for training, and therefore does not optimally engage proprioceptive capabilities.

A comprehensive overview of the reduced impact of aquatic plyometric training is provided by Donoghue et al.¹⁴ Generally, the impact of a jump increases with increase in ground reaction force (GRF). These authors demonstrated that performing jumping exercises (ankle hop, tuck jumps, countermovement jump, single-leg vertical jump and drop jump) led to reduced peak GRFs and impulses in aquatic environment as compared with that on land. This finding supports and extends earlier evidence that showed reduced GRFs during double-leg squat jumps in water.¹⁵ Moreover, Donoghue et al¹⁴ demonstrated that the rate of force development for ankle hops, tuck jumps, and countermovement jump in water were significantly lower than those on land—an indication of reduced impact of jump.

How should water depth be selected?

The level of water used for aquatic plyometric training is a critical controlling factor in determining ease of exercise. Earlier studies have been conducted on chest- vs. waist-deep water for aquatic plyometric training. Miller et al¹⁶ observed no added benefit of aquatic training in chest- vs. waist-deep water with regard to average force and power with the squat, countermovement and vertical jumps. However, water levels above the waist will lead to greater difficulty to balance and increased drag through water. This may decrease the stretch-shortening cycle reaction time for plyometric jumps. Donoghue et al¹⁴ used a¹.3 meter water depth to observe significant reductions in peak GRFs during aquatic plyometric training compared with land-based training. Moreover, Stemm et al’s¹⁰ previous study proved the effectiveness of knee-deep water for aquatic plyometric training. Therefore, the existing literature data supports the usage of knee- to waist-deep water for aquatic plyometric training sessions.

For education only; not a substitute for individual clinical judgment.