If you're training for the Phoenix Marathon in January, you're deep into it right now. Long run days are getting longer. Your legs are starting to feel it. And if you're like most recreational runners in Ahwatukee and South Tempe, your training plan is almost entirely running — which is a problem worth addressing before it becomes an injury.
I see this every fall: runners who trained hard all season arrive at the start line undertrained in the muscles that matter most in the second half of a marathon, and overtrained in ways that leave them fighting their own body. Cross-training at the gym isn't an accessory to marathon training — for most recreational runners, it's the thing that gets you to mile 26 feeling strong instead of surviving.
This is exactly what Justin specializes in, and it's why we've built a dedicated cross-training track for runners in our 85044 and 85044/85048 community who are targeting the Phoenix course.
Running is a single-plane, repetitive movement. Your body gets extremely good at that exact movement pattern — and progressively worse at everything else. Hip abductors, lateral glutes, hamstrings, and deep core stabilizers all tend to weaken in runners who only run, because running doesn't load them sufficiently.
Here's where this shows up in a race: miles 1–18 feel manageable. Mile 19, your form starts to break down. Your hips drop, your stride shortens, your back tightens up. That's not fitness failing you — that's specific muscular weakness. The muscles that hold your running form together, especially the glutes and hip flexors, are fatiguing. And once form breaks down, injury risk spikes.
Two gym sessions a week during marathon training, focused on the right muscle groups, addresses this directly. Runners who cross-train consistently run faster, get injured less, and recover better. There's a reason elite marathon programs have always included strength work.
Justin has trained runners at multiple experience levels, from first-timers doing the half to returning marathon veterans chasing a PR. His cross-training approach for runners focuses on four key areas:
These are the engine room of your running stride. Hip flexor mobility work combined with glute strengthening — single-leg hip thrusts, Bulgarian split squats, clamshells with resistance bands — directly improves stride length and reduces IT band and knee issues. Most runners are dominant in their quads and weak in their posterior chain. This fixes that.
Not crunches — anti-rotation core work. Planks, Pallof presses, dead bugs, and farmer carries build the kind of core stability that keeps your upper body from swaying and your pelvis from tilting when your legs are fatigued. This is the difference between clean form at mile 22 and hunching over a garbage can at the finish line.
Romanian deadlifts and good mornings, done with appropriate weight, build resilience in the posterior chain that running can't develop on its own. These muscles take a beating in the final miles of a marathon and most runners reach that stage without having ever loaded them under any real resistance.
The bike and the rower allow you to build aerobic capacity and push cardiovascular intensity without the impact stress of additional running miles. When your legs need recovery but your lungs want more, the gym machines give you a way to train smart instead of taking a day off.
Marathon training schedules are rigid in some ways — you can't push a 20-miler because you slept in. But strength cross-training has more flexibility, and 24/7 access means you can work it in wherever your weekly schedule has a gap.
The typical structure we see work well for Phoenix Marathon runners based in Ahwatukee and South Tempe: long run on Saturday or Sunday, two cross-training gym sessions Tuesday and Thursday, easy run or rest on other days. The gym sessions cap at 45–50 minutes — long enough to get meaningful work done, short enough not to compromise your run recovery.
If your work schedule is tight, early morning or evening gym sessions make this possible. Most of our runner members do their cross-training between 5:30 and 7am, before the workday starts.
If you're training for the Phoenix Marathon and haven't added cross-training to your plan, November is the right time to start — not December when you're in the taper. Come in for a free 7-day trial, meet Justin, and let him take a look at your training schedule. He'll tell you honestly what would help and what wouldn't be worth your time. No pressure to sign up for anything.
We're at 4855 E Warner Rd in the Basha's parking lot, open 24/7. Memberships start at $19.99 bi-weekly — less than most runners spend on gels for a long run.
No credit card required. No long-term contract. Try Anytime Fitness Ahwatukee free for a full week.
Or call (480) 900-1616 · 4855 E Warner Rd Suite 24-28, Phoenix, AZ 85044