Marathon Training: The Benefits of Back-to-Back Long Runs

Marathoners are increasingly adopting training strategies from ultrarunners, particularly the use of back-to-back long runs. This method helps build muscular endurance and teaches the body to perform under deep fatigue, which is crucial for race day Source.

Angie Spencer, an RRCA- and USATF-certified run coach, notes that this technique familiarizes runners with intense fatigue, enhancing both physical and mental resilience. Jason Fitzgerald, another USATF-certified run coach, highlights it as an advanced strategy beneficial for experienced, performance-oriented runners aiming for specific race times.

What Are Back-to-Back Long Runs?

A back-to-back long run consists of two runs, each lasting at least 90 minutes, performed on consecutive days. The period between the first and second run should allow for a night's sleep and adequate recovery and nutrition.

Benefits for Marathoners

Marathoners use this method not simply to increase mileage, but to improve their durability. Durability refers to the ability to maintain pace, form, and efficiency as fatigue accumulates late in a race.

Enhanced Durability and Fatigue Resistance

This training approach develops fatigue resistance, improves aerobic capacity, and increases tolerance for extended periods on feet. Spencer also points out the significant mental benefits, as runners learn they can push through discomfort.

Simulating late-race fatigue, especially in the last six to eight miles of a marathon, is a key advantage. This helps athletes mentally prepare for the most challenging parts of a race.

Targeting Specific Race Demands

Coaches can use the second long run to focus on specific stimuli. For example, an athlete training for a downhill marathon might incorporate downhill efforts into their second long run, which are particularly taxing on the legs.

Who Should Consider Back-to-Back Long Runs?

This advanced training technique is not suitable for all runners. Coaches carefully assess a runner's experience, training volume, injury history, and recovery capabilities.

Advanced and Dedicated Marathoners

Spencer recommends back-to-back long runs for seasoned runners who have completed at least four marathons in the past two years without injury. These individuals typically have a strong aerobic base and consistently manage training stress well.

Fitzgerald advises that runners should first establish a consistent mileage base of 50 to 60 miles per week and be able to comfortably complete an 18- to 20-mile long run. This foundational endurance reduces injury risk when increasing training demands.

Ultrarunners in Training

Individuals transitioning from marathon to ultramarathon training can also benefit. Spencer uses these runs to bridge marathon training cycles with ultrarunning preparation, sometimes treating a marathon race as a long run for a subsequent ultra event.

How to Implement Back-to-Back Long Runs

Coaches introduce back-to-back long runs gradually. Spencer might start with an easy four-mile jog after a long run, incrementally increasing the distance of the second run. An example progression over nine weeks could see the second run increase from 4 miles to 12 miles.

Fitzgerald suggests building mileage gradually for each effort and incorporating deload weeks to ensure proper recovery. He cautions against doing back-to-back long runs every week, as the stress on the body is high. Typically, runners incorporate only one to three such sessions per training cycle.

It is important to remember that increasing overall weekly mileage does not inherently increase injury rates. A study in the British Journal of Sports Medicine found that the risk of overuse injury is more closely linked to increasing the distance of any single long run by more than 10% compared to the longest run in the preceding 30 days. Gradually increasing mileage keeps this risk low Source.

According to Fitzgerald, increasing aerobic capacity through consistent mileage is arguably the most effective way to improve marathon performance. While hard workouts optimize the existing 'engine', higher mileage builds a larger engine overall.