Does Rucking Help With Running?

Rucking and running are two popular forms of cardio exercise that have some key differences but also share some similarities. So a common question among fitness enthusiasts is whether training with a rucksack can boost running performance. There are a few reasons why rucking could potentially help runners. The main one is that carrying extra weight in a rucksack forces your body to work harder. This can build strength and endurance in the muscles used for running. Rucking also gets your heart rate up and improves cardiovascular fitness. And the activity helps strengthen bones and connective tissues that take a pounding during running. However, there are also some drawbacks to relying solely on rucking to train for running events. While rucking builds some running-specific muscles, it misses others like the calves. The movement patterns differ as well, with rucking involving more of a straight-line marching motion. This does not mimic the bounce and quick lateral motions of running. So in the end, rucking can provide some benefits but is not a full replacement for actual running in training for races and events. The ideal approach is likely a combination of both rucking and running workouts.

Muscle Building

One of the main proposed benefits of using rucking for running is the muscle building it stimulates. Having strong leg and core muscles is important for running efficiently and avoiding injuries. Rucking with a weighted backpack forces the body to work against resistance. This can help build strength in muscles like the glutes, quads, hamstrings, hips, and core. These are some of the prime movers used when running. Studies show that adding load during walking workouts increases muscle activation significantly compared to normal walking. The extra resistance recruits more motor units in muscles like the erector spinae and gluteus medius. This muscle-building stimulus from rucking may produce some crossover benefits for running strength and economy. Stronger running muscles allow you to maintain speed and form for longer periods. However, it is worth noting that rucking does not necessarily target all the important running muscles equally. The calves, for example, are less activated than during running. So rucking alone is not enough to build maximal running-specific strength.

Cardiovascular Fitness

Another major benefit of rucking for runners is the cardiovascular training stimulus. Any form of extended cardio exercise that elevates heart rate is helpful for building VO2 max and endurance. Rucking with a heavy load requires significant energy expenditure. According to research, carrying a load equal to 30% of body weight during walking more than doubles the metabolic cost. This pushes the cardiovascular system and lungs much harder than normal walking. The American Council on Exercise found that a 155-pound person rucking with a 45-pound pack burned over 400 calories in just 30 minutes. This is on par with the calorie burn of a moderate jog. So using rucking intervals in training provides runners with a strenuous cardio workout. Over time, this can boost VO2 max, which measures the maximum oxygen uptake during exercise. Having a higher VO2 max allows runners to maintain faster paces without gassing out. However, rucking may not entirely replicate the specific cardiovascular adaptations of running itself. The vertical oscillation and impact involved in running produce different demands. So a combination of both types of training is ideal.

Bone and Connective Tissue Strength

Runners must contend with the constant impact forces from their feet striking the ground hundreds of times per mile. The cumulative effect can take a toll on bones and connective tissues. Rucking may provide a way to build impact tolerance and strength in these areas with lower-intensity loading. Walking with a weight vest or backpack produces cyclical impact forces throughout the body with each step. According to studies, this dynamic load strengthens lower body bones and connective tissues more effectively than static weightlifting. The controlled impact may stimulate beneficial adaptions in areas like bone mineral density. Over time, rucking could potentially help runners withstand the high-impact forces generated during training and races. Stronger bones and connective tissues in the legs and hips may translate to better injury resilience. However, it is not clear if the impacts from rucking are similar enough to run to produce full carryover. Rucking involves slower loading of a singular foot, rather than the quicker 1-2 impact of running strides.

Differences From Running

While rucking has some crossover benefits, it is not a perfect substitute for running-specific training. There are a few key differences: Movement PatternsRucking involves maintaining a steady marching pace, with mostly linear motion of the legs. Running requires more multi-directional movements and quick acceleration/deceleration. The bounce and mechanics of the running gait work different muscles. Impact ForcesAs mentioned earlier, the impacts from rucking differ from the repetitive foot strikes while running. The load is transmitted differently through the body. This may limit the carryover for impact tolerance. Muscle RecruitmentAlthough rucking uses many of the same lower body muscles, the lack of elastic recoil from tendons and different postures recruits them differently. Running relies more on explosive power from muscles like the calves. Cardiovascular DifferencesThe metabolic demands vary between rucking and running. Running produces more rapid oxygen flux and requires meeting higher cardiac outputs. So running likely produces superior VO2 max benefits. So while rucking and running share some general benefits, the specifics of each activity make them less interchangeable for training. Combining both is better than only rucking for runners.

Training Recommendations

Based on the analysis above, here are some evidence-based recommendations for effectively incorporating rucking into running training:

• Use rucking as supplemental training 1-2 times per week at most. Running should still make up the majority of workouts.

• Focus on low-to-moderate weight rucking to avoid overloading the body. Aim for 10-20% of body weight in the pack.

• Keep rucking sessions short to medium duration, between 20-60 minutes. Avoid going so long that running muscles become overly fatigued.

• Allow for proper rest and recovery after rucking to assimilate the strength gains before harder running workouts.

• Treat rucking as higher intensity strength training and reduce the running volume a bit to compensate on those days.

• Use rucking early in training cycles to build a strength base, then transition to more running-specific work.

• Combine rucking and running in the same session, like doing a moderate ruck then finishing with a fast run.

• Focus on maintaining proper upright posture and gait mechanics when rucking to maximize carryover.

Following these guidelines can help balance the benefits of rucking and running. Rucking 1-2 days per week in moderation may boost strength and resilience for runners. But running itself should still make up the bulk of the training program.

Sample Training Plan

Here is a sample weekly training plan that incorporates rucking alongside running:

Monday

• Long run - 7 miles easy pace

Tuesday

• Rucking - 30 minutes with a 15lb pack

Wednesday

• Intervals - 8x400m @ 5k pace with 2 min rest

Thursday

• Cross-training - 30 minutes cycling

Friday

• Tempo run - 4 miles @ 10k pace

Saturday

• Hills - 8x100m hill sprints

Sunday

• Rest

This schedule allows for one day of rucking at a moderate weight and duration early in the week. This is supplemented with key running workouts - a long run, intervals, tempo, and hills. The rucking builds general strength while the running provides specificity.

Pros and Cons of Rucking for Runners

Here is a quick summary of the main pros and cons of incorporating rucking into running training:Pros:

• Builds lower body strength and endurance

• Elevates heart rate for cardio conditioning

• Provides low-impact load to strengthen bones/connectives tissue

• Breaks up training monotony and reduces injury risk

• Helps recruit new motor units and muscle fibers

Cons:

• Does not replicate running-specific movement patterns

• Less effective for certain muscles like the calves

• Metabolic demands differ from high-intensity running

• Can fatigue muscles needed for key running workouts

• Overdoing rucking volume can lead to overtraining

Conclusion

Incorporating some supplementary rucking into a running training program can provide several benefits. The extra load stresses the muscles and cardiovascular system in ways that support running performance. However, rucking is not as running-specific as actual running workouts. So it should be used in moderation to complement a running-focused training plan. 1-2 mid-to-short duration rucking sessions per week is a good starting point. Being smart about balancing running and rucking training stress will allow you to get the best of both worlds - building overall strength and maintaining running-specific fitness. This can translate to new levels of speed, endurance, and durability on race day.