As many of you know, carrying around a heavy load is pretty much a required aspect of many jobs in the military or tactical community. PPE alone can weigh upward of 8-10kg (17-22lbs) and that is not considering all of the other shit you hang from the MOLLE like ammo, food, water, etc.

In fact, studies looking at load carriage in the military show a range of 13kg (Roman Legionnaires) to upwards of 60kg (modern airborne infantry) along with a number of weights in between depending on the mission.

So naturally, a question I receive on a regular basis is: “Should I train with a vest (body armor or otherwise) and if so, how is it going to benefit my training?”

And that is the question I want to explore here today.

As I’ve mentioned before my training philosophy revolves around getting the maximal amount of benefit from the minimal amount of training so I’d like to see some evidence that wearing around additional weight is actually worth more than just the increase in suck factor before I go about recommending you do it on a regular basis.

With that said, despite the title of the article, we are going to look at two different aspects of training with a weight vest including how it affects lower body power as well as how it affects running performance.

Improving Power

Some research has shown that just wearing the vest around (not necessarily while training) can be beneficial to improving agility in a population of otherwise healthy men. There is also a bunch of research on hyper-gravity (i.e. Adding weight to yourself) and its benefits on bone density, balance, and agility in elderly populations.

But how does that help you?

Well, it probably doesn’t.

However, the research does show that wearing a weight vest during training has been shown to improve power in athletes by upwards of 10% in as little as 3 weeks. The majority of these studies showed this result in trained populations (i.e. Those who are harder to get training adaptations out of) which means the benefits could be even higher for new(er) athletes.

To put that into a bit of perspective this 10% improvement was being compared to a resistance training only group where an 8% improvement was seen, however, it took upwards of 3-months to get that 8%.

Other studies have shown that loaded jump training (i.e. plyometrics with a weight vest) has been demonstrated to improve jump performance without an increase in injury risk. This obviously assumes proper jumping and landing mechanics as loading a dysfunctional movement pattern is typically a recipe for injury (eventually).

So it looks like adding some loaded power specific training can help improve power at a quicker rate, which isn’t all that shocking.

What is interesting is that Verkhoshansky (basically the father of plyometrics) found in his research that increasing load did not typically produce great effects.

Verkhoshansky experimented with adding load to the depth jump and found that increasing the load does not increase the working effect of the movement. He also noted that an increase in load will also lead to an increase in coupling time (time spent on the ground) mitigating the positive effects of the stretch-shorten cycle to some degree.

My interpretation here is that adding load (small at first and very gradually increasing) may, in fact, improve your plyometric ability BUT you have to move incredibly fast. As Verkhoshansky noted, spending more time on the ground (“coupling effect”) will lead to sub-par jumps. However, I’d hypothesize that if you can spend the time to learn how to move FAST by training the neurological system, then you might see some added benefits.

Conclusion

Adding a weight vest to your plyometric training may improve power to some degree but also comes with an increase in injury risk UNLESS you have great movement mechanics. Overall, I’d recommend you find something else to do (i.e. Just spend some time working in various (and progressive) plyometric movements unloaded as the research supports these!).

While loaded power training with a weight vest or your body armor is something to experiment with, it shouldn’t be a staple of your program. Although spending a bit of time learning how your body reacts to jumping and landing in your kit is probably a good thing, you will probably get an appreciation for that in your regular (non-gym) training.

Running

Now here is where the research is pretty much all over the place.

Some folks say that running with a weight vest will improve your sprinting performance while others say the exact opposite.

Let’s review some of the research (there isn’t a ton)…

Weight vest training with loads similar to body armor (8-10kg) was shown to improve VO2max and treadmill time to exhaustion more so than unweighted training but not significantly.

This was after a 6-week training program similar to what is seen at Marine Recruit Training. Although an increase in VO2max was seen, it wasn’t significant. Meaning, training without the vest will get you a pretty similar result. However, this study did find that treadmill time to exhaustion also increased, which (in my experience) can likely be attributed to the fact that walking on a steep treadmill without a vest is mentally easier than training with the vest so the effort seemed easier, leading to a slightly better result.

Not many other benefits were seen in this study. The authors noted, and I agree, that the loads used (8-10kg) were not sufficient for eliciting adaptations of the lower body musculature. Which basically means, when considering appropriate training loads you must consider how much weight is enough to overload the system.

While adding a 10kg weight vest will significantly reduce the number of pull-ups or push-ups the average person can do it will not slow them down much on lower body focused tasks like climbing a hill, walking of a steeply inclined treadmill, or performing squats and/or lunges.

There will be some effect but the loads will likely need to be increased and the adaptation will likely take much longer to be realized.

With that said, the optimal load for sprinting (or running in general) is likely loads that minimally affect running mechanics while still providing an overload stimulus to promote adaptations (Which might mean no additional load at all!).

In a study comparing two different weight vests (9kg & 18kg) it was found that the lighter vest resulted in much better kinematics and kinetics (i.e. more efficient movement).

This is important to note as one of the common things you hear out there on the internets about this topic is ”You should never run with a ruck or weight vest, it is terrible for your joints!”

However, this study noted that this may only be the case at higher loads (18kg+).

I would say that even then, it has to do with your ability to maintain efficient movement mechanics.

As a very well known strength coach named Dan John once said:
“It is not the squat that hurts your knees, it’s the way YOU squat that hurts your knees!”

While this study did mention that during the 18kg vest sprint significantly higher peak ground reaction forces were noted they also noted an increase in torso angle (a major fault in efficient running). So, we really can’t conclude that the load was the problem… The athlete was probably just too weak to handle it!

Being too weak was a theme of another study that looked at leg stiffness during loaded running.

According to the authors running with load increased leg stiffness which leads to an increase in peak vertical ground reaction force (force of your impact on the ground and the grounds equal and opposite reaction back into your foot).

This was caused by an increase in ground contact times which means that the athlete’s foot was on the ground longer and the force was being absorbed and eventually redirected into the next step. Much like adding load to your plyometrics, the longer you’re on the ground, the less benefit and more you have to work to stabilize the system.

Loaded running also showed greater hip, knee, and ankle flexion during the stance phase which was a cause of the body absorbing the force like a big spring.

Additionally, this study also noted that in general, the individuals observed ran in a more crouched position (i.e. poor posture) when they ran with a load.

Lastly, it was noted that carrying the additional load and increasing lower extremity joint flexion requires an increase in muscle activity and has a higher metabolic cost.

So what does this all mean?

Basically, this is all saying that running with a weight vest is hard.

And if you want to do it effectively then you need to make sure you are strong enough and conditioned enough to handle it. Because if you aren’t, it’s going to punish your mechanics and your body.

Conclusion

While the research is all over the map it seems as though spending some time running with a weight vest could be beneficial. However, as with anything else, when you increase the intensity of a movement mechanics are going to take a hit if you aren’t careful.

As one study mentioned above noted athletes running with a load showed a greater increase in torso angle (i.e. bending over at the waist) which we know is a major fault in the POSE methodology and typically caused by a weak midline. This creates all kinds of disadvantageous leverage and ultimately leads to inefficient running and lots of low back pain (a common complaint of many long-term military folks and LEOs wearing body armor all day long).

So, just like with all of your other aerobic training you should probably add in weighted training slowly and only occasionally while prioritizing strength development and mobility work (Especially if you have tight hips, a weak core/midline or both!).

So how should I work my weight vest or body armor into my training?

Slowly.

As we just examined, loaded running (or loaded training in general) can have some positive benefits.

However, as with any movement that we apply intensity to, mechanics will begin to break down faster leading to an increase in injury risk but also sub-par training adaptations. Which basically means you’ll be training, but won’t be getting much out of it.

Strength and conditioning must be the priority.

Once your running mechanics are dialed in and you are strong and able to handle the increase in load and/or intensity then adding in a weighted run every other week or so will be fine.

Just be sure to be constantly running through your technique checklist in your head as you go… When things start to break down or that weird ache or pain pops back up, then stop, recover for a minute, reset your mechanics and get back after it (Or end the session altogether!).

Here is a quick 2-week snap shot of what it could look like:

Week 1:

Monday: Strength & Conditioning Training
Tuesday: Short Interval Run (10 x 100m, :30s rest)
Wednesday: Strength & Conditioning Training
Thursday: Long Interval Run (5 x 800m, 3:00 rest)
Friday: Strength & Conditioning Training
Saturday: Strength & Conditioning Training
Sunday: 3M Tempo Run

Week 2:

Monday: Strength & Conditioning Training
Tuesday: Long Interval Run (3 x 1M, 4:00 rest)
Wednesday: Strength & Conditioning Training
Thursday: Short Interval Run (4 x 400m, 2:00 rest w/ 20# vest or body armor)
Friday: Strength & Conditioning Training
Saturday: Strength & Conditioning Training
Sunday: 5M Time Trial Run

Basically, if you are running 3 times per week (like above) you can add the weight vest or body armor in every couple of weeks on a different day (i.e. 1st time during the short interval, the 2nd time during the Tempo run, a 3rd time during the long interval). Just keep the rotation going and you should be good to go as long as your mechanics and your required/desired paces don’t take a major hit.

If your running technique sucks or you don’t know where to get started with a training plan I’ve got a few different options available to you:

  1. Sign up for the Free Strategic Endurance Mini-Course
  2. Grab the Strategic Athlete 5k Training Program (for improving your running abilities for any distance up to about 3-miles)
  3. Check out the 16-week Strategic Endurance Membership (Broken up into 4-week cycles designed to help you conquer different distances (5k, 10k, half-marathon, etc)

You can also shoot me an email with any questions you have about this stuff at any time. If you’d like me to review your running technique (FREE) again, just shoot me an email pj [at] strategicathlete [dot] com and I’d be glad to help!

Happy Training

Strategic Endurance

References

Clark, K., Stearne, D., Walts, C., & Miller, A. (2010). The longitudinal effects of resisted sprint training using weighted sleds vs. weighted vests. Journal of Strength and Conditioning Research, 24(12), 3287-3295.

Cross, M., Brughelli, M., & Cronin, J. (2014). Effects of vest loading on sprint kinetics and kinematics. Journal of Strength and Conditioning Research,28(7), 1867-1874.

Hanssen, I., Sheppard, J.M., Dingley, A.A., Chapman, D.W., & Spratford, W. (2012) Lower extremity kinematics and kinetics when landing from unloaded and loaded jumps. Journal of Applied Biomechanics, (28), 687-693

Rantalainen, T., Ruotsalainen, I., & Virmavirta, M. (2012). Effect of weighted vest suit worn during daily activities on running speed, jumping power, and agility in young men. Journal of Strength and Conditioning Research,26(11), 3030-3035.

Silder, A., Besier, T., & Delp, S. (2015). Running with a load increases leg stiffness. Journal of Biomechanics, 48, 1003-1008.

Swain, D., Onate, J., Ringleb, S., Naik, D., & Demaio, M. (2010). Effects of training on physical performance wearing personal protective equipment. Military Medicine, 175(9), 664-670.