Steady State Run: 45-Minute Aerobic Base Builder

Session Overview

This 45-minute steady state run is the cornerstone of triathlon run training. By maintaining a controlled, conversational effort throughout, you develop the aerobic engine that underpins everything from sprint races to long-course events. Intermediate triathletes should complete 2–3 sessions like this per week during the base phase, building volume before layering in intensity.

What You’ll Need

• Running shoes appropriate for your foot type
• GPS watch to monitor pace and heart rate
• Water or a short route with a water fountain for warmer days
• A flat to gently rolling route — avoid hills during a pure aerobic session

Warm-Up (8 minutes)

Begin with a 5-minute brisk walk or very easy jog, then perform dynamic stretches: leg swings, hip circles and ankle rolls. Spend the final 3 minutes jogging at a comfortable pace — this should feel almost embarrassingly easy. Your warm-up pace is not a reflection of your fitness; it’s an investment in a quality main set.

Main Set

Run for 30 minutes at a steady aerobic pace — this is Zone 2 effort, which means you can hold a full conversation throughout. Heart rate should be 65–75% of your maximum, or RPE 4–5/10. If your heart rate climbs above Zone 2 on a hill, slow down to bring it back — this is a disciplined session, not a tempo run.

• Minutes 0–10: Settle into your steady pace. It should feel comfortable to slightly easy — resist the urge to push.
• Minutes 10–20: Check in with your form: upright posture, relaxed shoulders, mid-foot landing, cadence around 170–180 spm.
• Minutes 20–30: Maintain your effort — if you’ve paced correctly, this final third should feel no harder than the first.

Cool-Down (7 minutes)

Walk briskly for 3 minutes immediately after stopping to bring your heart rate down, then perform 4 minutes of static stretches: standing quad stretch, lying hamstring stretch, hip flexor lunge and calf stretch. Hold each for 30 seconds per side. Don’t skip the cool-down — it accelerates recovery and reduces next-day stiffness.

Coaching Notes

• The most common mistake in base training is running too hard. If you finish the session feeling like you could have gone further, you’ve nailed it.
• Run to heart rate zone rather than pace — on warm days or after a hard bike session, your pace will naturally be slower at the same effort level.
• To make this session easier: slow down and reduce to 25 minutes. To make it harder: extend to 50–55 minutes at the same effort, not a faster pace.
• Keep a training log — if your pace at the same heart rate improves over 4–6 weeks, your aerobic base is building exactly as intended.