Chicago's home for elite underwater training. We build breath control, composure under pressure, and nervous-system regulation for everyone from weekend athletes to first responders, pro teams, and tactical operators.
Whether you're stepping into the pool for the first time or building a training program for your unit, team, or company — there's a path here.
Weekly coached sessions at the UIC Natatorium. Build CO₂ tolerance, breath-hold capacity, and water confidence in a supportive group environment. Scalable for all levels.
Private programming designed for first-responder units, professional and collegiate athletic staff, dive teams, and corporate performance groups. Built around your mission, scheduled around your shift.
See the live class schedule and book directly. Sundays at the UIC Natatorium plus added sessions throughout the week. New to DEF? Look for any class tagged "All Levels."
The Deepend methodology was developed by U.S. Military special operators and is informed by selection-pipeline training. We adapt it for the professional environments where breath, composure, and decision-making under stress actually matter.
Underwater confidence, water-survival skill-building, and stress inoculation programming for police, fire, rescue, and tactical units.
Off-season conditioning, in-season recovery, and breath-capacity training for professional and collegiate rosters. Low-impact, high-yield work.
Programming for working divers, aquarist staff, and lifeguard programs that need consistent underwater fitness and confidence-building.
Private sessions for executive teams, leadership offsites, and corporate wellness programs. Stress regulation that translates into real-world decision-making.
Competitive swimmers, certified divers, and underwater athletes who've put in the hours. Every coach is trained in the full DEF methodology and committed to building water confidence from the very first session.
Founder of DEF Chicago and a certified free diver and scuba diver. Matt brings a taste of the ocean to the Midwest, leading every Sunday session at the UIC Natatorium with a focus on breath mastery, composure, and water confidence for athletes of every level.
Competitive swimmer and CrossFit national-level competitor. Mel pairs elite conditioning with technical pool work, helping students build CO₂ tolerance, capacity, and the kind of relentless composure that wins both in the water and out.
Lifelong competitive swimmer and underwater enthusiast. Laura coaches with the calm authority of someone who has lived in the pool — patient with first-timers, sharp with seasoned athletes, and obsessed with the technique that turns hesitation into confidence.
Active United States Coast Guard, open-water competitor, and underwater enthusiast. Augie brings real-world tactical aquatic experience to every session — the kind of training that prepares people not just to perform in the water, but to respond when it matters.
Competitive swimmer with deep Illinois roots and a longtime love of the water. Ed pairs the discipline of high-level training with a coach's patience, helping athletes of every level get more comfortable, more efficient, and more confident underwater.
Whether you're booking your first Sunday class or scoping a multi-session program for your agency, drop us a line. We'll respond within one business day.