Why Physically Fit Adults Struggle with Swimming – And How to Fix It
Dec 19, 2025
Article by Nicole Fairfield
Many physically fit adults — including runners, lifters, and tactical athletes — struggle with swimming despite being strong and capable on land. This often leads to confusion and frustration for both the swimmer and the instructor. The issue isn’t a lack of strength or fitness — it’s a mismatch between the body’s natural response to water and the specific skills required for swimming. Understanding these barriers is key to unlocking progress and building confident swimmers.
The Disconnect Between Fitness and Swimming Ability
Being physically fit does not automatically translate to being a strong swimmer. This is because swimming requires:
- Water Acclimation – Developing comfort and balance in the water.
- Breath Control – Managing CO2 buildup and breath timing.
- Buoyancy and Body Position – Adjusting to muscle density and the lack of ground support.
- Neuromuscular Coordination – Engaging the right muscle groups for efficient propulsion and flotation.
1. Water Acclimation Is a Learned Skill
Fit adults are used to operating in environments where they have control and stability (land). Water removes that stability, triggering a stress response (Pendergast et al., 2015).
If the body is not comfortable with the feeling of floating or the sensation of water pressure, it’s impossible to relax and focus on technique.
Solution: Start with acclimation drills — back floats, face submersion, and breathing exercises.
2. Breath Control and CO2 Tolerance
Fit adults often have large lung capacity but low CO2 tolerance in water. Panic occurs when CO2 builds up faster than the body is used to processing it.
Studies have shown that trained swimmers have a higher tolerance for elevated CO2 levels than land-based athletes due to specific respiratory adaptations (Lindholm & Lundgren, 2009).
Solution: Use exhalation-based drills to train the body to handle higher CO2 levels and maintain calm breathing patterns.
3. Buoyancy and Body Composition
Muscle is denser than fat, which makes fit adults more prone to sinking. Men, in particular, with high muscle mass and low body fat, have difficulty staying afloat (Pendergast et al., 2015).
Buoyancy is affected by body fat percentage — higher fat percentages increase natural flotation (McArdle et al., 2015).
Solution: Teach proper sculling and body position adjustments to compensate for lower natural buoyancy.
4. Neuromuscular Coordination
Swimming isn’t about strength — it’s about efficiency. Strong athletes often overuse muscle rather than learning how to work with water resistance.
Studies show that experienced swimmers have higher levels of proprioceptive awareness and balanced muscle activation compared to land athletes (Toussaint & Beek, 1992).
Solution: Focus on smooth, controlled strokes and proper kick technique.
Why Treading and Floating Are Problem Areas
Many tactical athletes and lifeguards struggle not with swimming — but with treading water and floating. This is because:
- Treading requires a strong and coordinated rotary or whip kick.
- Floating requires both body balance and relaxation — hard to achieve if the body is tense or sinking.
Incorporating Jose-Luis Gallagher’s Dual Boards
Jose-Luis Gallagher’s Dual Boards by Rip Current Sports offer a powerful tool for addressing this problem:
- The upper board helps relax the arms and focus on breath control.
- The lower board engages the legs and core, building strength for effective treading.
- Combining both improves overall buoyancy and balance while increasing kick strength.
For lifeguards training for the American Red Cross brick swim – mastering a strong and coordinated whip or rotary kick is essential. Dual Boards provide targeted strength training for this exact movement.
Action Points for Instructors
- Start with Water Acclimation – Floating and controlled breathing before swimming.
- Introduce Breath Control Drills – Exhale fully, reduce panic response.
- Train Body Position and Balance – Teach sculling and center-of-gravity adjustments.
- Build Kick Strength – Use Dual Boards to isolate leg and core strength; without Dual Boards, use water dumbbells or a kickboard under each arm.
- Refine Neuromuscular Coordination – Focus on smooth, controlled strokes.
Conclusion
Understanding why fit adults struggle in the water allows instructors to address the root causes — not just the symptoms. By focusing on water acclimation, breath control, buoyancy, and proper technique, instructors can transform confident athletes into strong swimmers. Tools like Dual Boards can accelerate this progress by building both strength and control in a targeted, effective way.
With the right approach, you’re not just teaching someone to swim — you’re helping them become a swimmer.
Additional Resources
For more details, I have created a one-pager and a presentation based on this article. These resources provide actionable steps and training strategies to help instructors address the key challenges outlined here. Feel free to reach out for access or more information.
References
- Lindholm, P., & Lundgren, C. E. (2009). The physiology and pathophysiology of human breath-hold diving. Journal of Applied Physiology, 106(1), 284-292.
- McArdle, W. D., Katch, F. I., & Katch, V. L. (2015). Exercise Physiology: Nutrition, Energy, and Human Performance. Lippincott Williams & Wilkins.
- Pendergast, D. R., Moon, R. E., Krasney, J. J., Held, H. E., & Zamparo, P. (2015). Human physiology in an aquatic environment. Comprehensive Physiology, 5(4), 1705-1750.
- Toussaint, H. M., & Beek, P. J. (1992). Biomechanics of competitive front crawl swimming. Sports Medicine, 13(1), 8-24).
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