When you are trying to build a foundation of cardio endurance as well as muscle stamina for future challenging selection programs, remember that most selections are a "running man's game" or rucking, depending upon your service selection. Here is a workout we do during our running / high repetition cycle that we call Spec Ops Leg Day:
Run 1-2-mile warmup (run or ruck) Repeat 4 times Run 1/2 mile fast pace Squats 1 min Walking Lunges 1 min Fireman Carry 50m Stretch 1 min Run 1 mile of 100m fast / 50m slow. (OR Run in soft sand or hills / bleacher sets mixed into 4-5 miles of running) THEN: Swim and Leg PT
Try the Life Saving Lunges if you have a partner, but otherwise swim with a shirt in each hand for 25m x 10 / lunge 25m x 10. This is a great way to mix in a lifesaving skill (tested in many programs) as well as to build up leg endurance. Here is how to set up the Swim and Leg PT: (See video link too) Repeat 5 times 25m rescue buddy 25m walking lunges back to deep end 25m buddy rescues you 25m walking lunges back to deep end Now, the focus is swimming endurance and technique with and without fins. Swim 500m without fins (freestyle or side stroke) Swim 1500m with fins. If NO SWIM - do a 45 minute ruck for max distance.
All of these elements (run, swim, rucking) are part of what we call the Spec Ops Triathlon. We actually run these quarterly as a fundraiser for a local community center if you are interested in ever testing out these critical skills of Special Ops Fitness.