New Features in GymAware Lite 2.7

Simple Export

Export of set based statistics to CSV file. Added to the review all sets option. – email yourself the set stats. Note if you want a full featured export, you will need one of the  GymAware online services. 

New total summary row on the bottom of the rep stats table. Use this to  see time under tension. – iPad only

Graphing

Position and parameter graphs have been improved (see below)

The blue line (above) is bar postion and the red line is the measurement parameter, in this case it’s Velocity.

Grey shading is the concentric phase of the lift as determined by the Heuristic Advanced Rep Detection (HARD) system.

Velocity/Position Analysis

This is for users who wish to identify the ” sticking point” or where velocity slows during the concentric phase

As with the graphs on the online account, we show both the concentric and eccentric phases.

In this example there are 3 reps. There is a slight velocity drop at 16-20cm down from full extension on the bench press.

Zero postion is at full extension, whereas -46cm is on the chest – shown as -0.4.

Custom Rep Detection

Adjust minimum movement thresholds for each individual exercise. Users wanting to detect reps on lifts with restricted movement (such as rehabilitation to testing to the elderly)  can now adjust this to suit their own needs.

To set the threshold, select exercise setup and click on the blue circular arrows to set minimum threshold. See below.

Then, set value in cm.

Reps won’t be counted unless the bar moves past this minimum range.

Also note that with each addition rep the bar needs to reach at least 75%  of  the previous rep to be valid.

Support for Japanese language has been added.

Many practitioners use GymAware to measure power velocity and height in jumps.

Jumps are popular because they are a quick, non-invasive exercise for checking the performance of the athlete.

How to Measure Jumps with GymAware

First you need to design a test protocol that is easy to replicate and that reduces sources of variability. Once you have decided on a protocol you need to make sure your athletes understand it and that they stick to it. Otherwise you will lose the ability to compare results over time.

Hot Tip If you are measuring jump height make sure the athlete is completely ready to jump (standing tall with feet flat) before you press the START button. Pressing the START button sets the zero for jump height calculation. Distance above this position is considered to be jump height, distance below is dip.

There are a few things to consider in determining the protocol and setup you use.

• Reducing the effect of technique
• The skill and maturity of the athlete
• The frequency of testing

A good way to reduce the effect of technique is to constrain arm swing by using a broom handle as a barbel. This also makes a good point to attach the GymAware tether.  You can place the Power Tool on the floor beside the athlete so that the unit is clear of their feet. One point to note here though, is that the athlete needs to be instructed( and you need to check for) any tilting of the bar during the jump, as this will produce errors.

To avoid these errors you can mount the Power Tool above the athlete using the Power Tool mounting bracket. The unit will detect that it is mounted upside down and will automatically compensate.

Please note that we don’t recommend relying solely on the magnets to secure the Power Tool above the athlete. The bracket can be screwed to the unit then securely mounted to the ceiling.

Another quick option is to place the unit between the legs and attach the tether to a belt on the athlete. This makes some athletes nervous at first as they fear landing on the unit when jumping. Most athletes get used to this and have no problems, as the natural way to jump is with feet shoulder width apart.  If you still have concerns you can recess the Power Tool into a platform.

This makes some athletes nervous at first as they fear landing on the unit when jumping. Most athletes get used to this and have no problems, as the natural way to jump is with feet shoulder width apart.  If you still have concerns you can recess the Power Tool into a platform.

Thanks to team at ASCA for another great conference!

Thanks to the presenters and to everyone that attended our inaugural Icebreaker Seminars. We were humbled by the quality of the presentations and by the great audience reception and discussion.

Three great presentations and a friendly crowd!

We had a good time in our booth, shared again with Swift, lots of visitors, lots of new ideas of where to tack our products next!

See you again next year!

Mladen Jovanovic is a physical preparation coach from Belgrade, Serbia, currently serving the position of head physical preparation coach in Hammarby, Soccer Club from Stockholm, Sweden. He is has a blog called Complementary Training and is an expert GymAware user!

Estimating 1RM using load-velocity relationship

There has been recent interest in using load-velocity relationship in predicting 1RMs, especially now when the availability of LPTs (Linear Position Transducers) and accelerometers is increasing, along with their ease of use.

What has been widely used up to this point is load-endurance relationship, estimated by repetitions to failure. On the following picture is the visual representation of that relationship using data from Dan Baker. You can also see read more on that relationship here.

Before I commenced this little self-experiment and a play with GymAware I wanted to do a short literature review, so I can avoid pitfalls identified by the researchers. I have found couple full papers by using Google, Google Scholar and PubMed and I am reviewing them here.

Jidovtseff et al. (1) suggests measuring average velocity (AV) and not peak velocity (PV) for two reasons. First AV better represents the ability of the subject to move the load through the entire concentric phase. Second, AV decreases linearly with increasing load, making mathematical analysis easier.

Jidovtseff et al. (1) recommends measuring AV at 3 to 4 increasing loads with 3 to 5 separate trials at each load and a full recovery to get subject’s best performance. It is unnecessary to use very high loads, but the decrease in AV between the lightest and heaviest loads should reach at least 0,5 ms^-1.

From Bosquet et al. (2)

• Some commercial devices allow estimating 1 RM from the force-velocity relationship.
• These estimations are valid. However, their accuracy is not high enough to be of practical help for training intensity prescription.
• Day-to-day reliability of force and velocity measured by the linear encoder has been shown to be very high, but the specific reliability of 1 RM estimated from the force-velocity relationship has to be determined before concluding to the usefulness of this approach in the monitoring of training induced adaptations.

From Jidovtseff et al. (4)

• Prediction of 1RM appears to be dependent on mathematical method, selected parameter (peak velocity versus average velocity), device, exercise and equipment.
• It is more accurate to predict the 1RM from the V1RM (M2) than from the 1RM-Ld0 relationship (M1)
• For traditional exercises like bench press and squat used with free weights or guided barbell the use of load-velocity relationship to predict the 1RM appears as accurate as traditional repetition-to-failure method and present the advantage of assessing at the same time the muscular velocity that is a very important component in many sports

So after this quick review I decided to do a short experiment using bench throw in the Smith Machine from a static position (3seconds pause at the chest), box squat (with 3 second pause on the box – not relaxing, just touching it) and bench press (again same 3 seconds hold). Concentric contraction was done with maximum intention to lift explosively.

For each load (kg) I did 3 trials and pick-up the best one as a score. I have also calculated CV% (coefficient of variation) to see which method is more reliable. The recovery in between trials was from 1 to 3 minutes.

Here is the short video I did while taking the data:

 On the following table is the data for both Mean Velocity and Peak Velocity.

 Correlation between best scores of Peak Velocity and Mean Velocity is 0,974. Average CV% (coefficient of variation) for sets calculated with Mean Velocity is 2,38% and for Peak Velocity it is 3,37%, which is 42% bigger.

Based on the recommendations from the references and based on the lower CV and thus typical error, I decided to use Mean Velocity as a method of calculating velocity.

Bench Throw

Apparently we have crappy Smith Machine, since my velocity is higher on the bench press than bench throw with the same weight. The path in the Smith Machine is leaned towards me, and maybe there is some friction adding up to the resistance (plus I assumed that unloaded bar is 20kg and it might be more). Anyway, here is the graph and linear regression:

You can pretty easy create the linear regression formula in Excel. All you need is to create a Scatter chart (go to Insert Tab -> Scatter) and select weight data (in this case 20, 40 and 60kg) as X variable and velocities associated with those weights as Y variable.

When you are done with this you can add regression line. You need to click on the chart, then go on the Excel Ribbon to Chart Tools -> Layout -> Trend line -> More trend line options. The window will pop-out and you should select Linear button and Display Equation on Chart box. That’s it.

From the linear regression formula we can calculate LD0 (load when velocity is zero) and MV0 (velocity when load is zero).

LD0 = 112,83 kg

MV0 = 1,52 ms ^–1

Bench press

On the following picture you can see scatter plot and linear regression equation.

From the linear regression formula we calculate

LD0 = 115,64 kg

MV0 = 1,62 ms ^–1

Please note that LD0 is NOT my 1RM. The question is what is the velocity at 1RM attempt (for me)? I would say the 100kg pause bench (3’’ pause) was pretty tough already and the mean velocity was 0,19-0,23 ms ^–1.

As we know from the practice, some lifters have pretty fast 1RMs while others have slow 1RMs attempts („grinders“). I wonder why. It might be related to relative strength (for example 1RM of one lifter is 100% his bodyweight, while other might have 1RM of 180% his bodyweight), but even if this is taken into account people with same relative strength might differ how fast are they pushing in their 1RM attempt. Maybe it is CNS quality, fiber dominance, leverage, force curves and sticking point etc. It would be very interesting study to find out.

Back to my example. Mann (5) suggested the following zones:

I would call his absolute strength the ‘grinding zone’. For me, I might pull out 0,15 ms ^–1, so I might calculate how much would that be in kg.

1RM (Load @ 0,15 ms ^–1) = 104.92 or 105kg.

Nothing to be proud off though. Remember that this was a pause bench, with no spotters and not psyching up. (Note to myself – stop using the excuses and get back to work).

If I assume that this is my 1RM, I can now calculate weights that could/should be used for development of different strength qualities (see Mann’s table)

This approach is novelty for me (and I guess to a lot of strength and conditioning coaches out there as well to power and strength athletes too) since before easily accessible LPTs like PowerTool/GymAware we haven’t even consider velocity as variable. This provides one whole another dimension to strength training programming, prescription and monitoring. I will expand more on this idea later. Let’s check out my squat performance.

Squat

Finally something I could be proud of – at least by formulas.

Although Jidovtseff et al. (1) recommends that the velocity difference between lightest and heaviest load should be more than 0,5 ms-1 for more precise linear regression, in my case the difference is 0,36 ms-1 (0,95 @60kg – 0,59 @120kg). I should have done one more set with 140kg to make regression formula more precise.

Anyway, now we can calculate

LD0 = 220,3 kg

MV0 = 1,322 ms ^–1

Same as with the bench press example I would need to know my 1RM velocity to calculate 1RM load. These differ between exercises . Something is telling me that velocity at 1RM attempt in squat is higher than 1RM attempt in bench press (due longer path?). For the sake of example I will use 0,25 ms ^–1

1RM (Load @ 0,25 ms ^–1) = 178,66 kg

If I plug this into Mann’s velocity categories this is what we get:

Novel Method – Using Velocity instead/together with 1RM or LD0

What I like with this method of calculating 1RM is that you don’t need to do 1RM attempt and you can actually prescribe load in form of load at certain velocity. For example – perform 2 reps at load that corresponds with 0,3 ms^-1, or you can track load at 0,5 ms^-1 over time instead or 1RM or 3-5RM. Of even better you can prescribe training intensities not on 1RM but rather at some decent velocity that is close to 1RM (1RM = Load @0,25 ms^-1).

This is also interesting especially in power sports and/or mixed sports (like team sports and sport games) where we need to evaluate strength with good technique and speed, instead of grinding efforts. I would be more interested to see strength performance at certain velocity of the bar, instead of grinding attempts which could also have higher injury potential and can cause a lot of soreness the next day.

For this reason I think strength-velocity profiling might be a great idea. The question is how to use it to prescribe training loads, instead of only tracking 1RMs and/or strength at certain velocity.

First method which everyone is familiar with is to use 1RMs to prescribe training intensities. There is couple of ways of estimating 1RM:

• Actually measuring 1RM by 1RM testing
• Estimating 1RM from repetitions to failure (strength-endurance relationship)
• Estimating 1RM from load-velocity relationship (just described)

It can be said that reaching of the different strength training goals (and thus motor qualities) is based on utilization of different loading protocols (weight, reps, sets, tempo, rest, etc.) or methods. So, each of the methods aimed at reaching different strength training goal utilize different loading protocols. This is based on the repetition continuum, or the ’idea’ that different goals can be achieved utilizing different reps per set.

There is a dynamic interaction between the variables of reps, sets and loads. The load used (% of 1RM) ultimately determines how many reps per set are done. Reps per set (or set time) ultimately determines how many total sets must be done. The interaction between the three will affect what adaptation is seen. Although not all authorities agree, there is thought to be a continuum of adaptations which may occur with different repetition sets. This continuum is called repetition continuum and it is based on percentage of 1RM.

Example of using this continuum might be doing sets with 60-85% 1RM for hypertrophy and 85-100% for strength development, although this is a little oversimplification (please make sure to check Lyle McDonalds Categories of Weight Training or mine Planning the Strength Training). There are a lot of tables that prescribe optimal intensity, reps and volume (like Prilepin, Sheiko, etc) for reaching goals in maximum strength, strength-speed, speed-strength, hypertrophy, strength endurance, etc., so I will not cover them here.

What is common with all this methods is that they use 1RM (or %s of 1RM) for prescribing load. If I apply this approach to my bench press data this is what I get:

As you can see we can use % of LD0 and/or 1RM to prescribe training zones. Using linear regression formula I can easily find velocities associated with each zone (in my case for the pause bench press) which I can use as regulator of training – or in other words I can modify the training if I am tired and out of zone, or if I show improvements I could re-test the strength-velocity profile and prescribe new loads.

According to González-Badillo et al. (3) is your velocity at given load (in kg) improve for more than 0,07 – 0,09 ms^-1 that corresponds to your 1RM improving for 5%. This again depend on the lifter, but it is a good baseline.

Using velocity in this way, one could stay with the certain weight until he masters it (and it this case that means improving average velocity of the lift). This shouldn’t be seen as a platoue, but rather training load at which you try to improve you power output.

What might be interesting novel method is to use velocity to prescribe loads. For example, one might use percentages of MV0 (estimated velocity when resistance is zero) or using velocity at 1RM. Check the following table where I used percentages of MV0 to create zones of intensity:

 It is basically the same table as above, but I have using MV0 instead of LD0 to devise zones. Another interesting idea might be to use percentage of velocity at 1RMs to prescribe training load. Having velocity variable increase our option (and that sometimes confuses more than it gives freedom though).

 I hope that in some future instalments I might give more precise instructions on how to prescribe training, monitor/regulate and progress over time using these variables. Till that time get the GymAware and start experimenting.

Editors Note: There is an automated way of doing this in GymAware Pro Online see this post for details 

REFERENCES

1. Jidovtseff, B, Harris, NK, Crielaard, J-M, and Cronin, JB. Using the load-velocity relationship for 1RM prediction. J Strength Cond Res 25(1): 267-270, 2011

2. Bosquet , L, Porta-Benache, J, and Blais, J. Validity of a commercial linear encoder to estimate bench press 1 rm from the force-velocity relationship. Journal of Sports Science and Medicine 9, 459 – 463. 2010.

 3. González-Badillo, J,J, Sánchez-Medina, L. Movement velocity as a measure of loading intensity in resistance training. Int J Sports Med (31): 347 – 352. 2010

 4. Jidovtseff, B, Cronin, J, Crielaard, J-M, Villaret, J, Harris, N. 1RM prediction and load-velocity relationship. From Book of Abstract: 8th International Conference on Strength Training. Oslo, 24th – 28th of October, 2012.

 5. Mann, B. Power and Bar Velocity Measuring Devices and their use for Autoregulation. NSCA Hot Topic series. Downloaded 1.11.2012 from http://www.nsca.com/WorkArea/DownloadAsset.aspx?id=707

Power and Force, Velocity Profile

GymAware Pro Online users can estimate 1RM very simply by collecting results over a range of lift weights and then selecting this report.

In the figure below the the Y axis is both mean Power in Watts and mean Force in Newtons, and the X axis is mean Velocity.

In this case an estimate of 1RM is calculate using a linear regression of the Force/Velocity data  to the point where velocity = 0msec^-1.  The result above of 154.78 kg is converted from 1516.8N at x = 0 on the graph.

Mladen Jovanovic has written a great post where he tries this approach out on himself. He also covers the research behind the approach and offers some advice on the data collection protocol. It’s a must read for anyone interested in using lift velocity for estimation of 1RM.

Last Chance to upgrade to the new iOS Power Tool –

Offer closes 1st January 2013

Upgrade Pricing

Version 4 Power Tool upgrade – AUD$ 650 Ex GST

These units can be upgraded with a new motherboard to be identical to the version 5 Power Tools. Your unit will be upgraded, refurbished and calibrated to version 5. All you will need then is an iPhone, iPad or iTouch to work with your new Power Tool 5.

Version 3 Power Tool Trade In – AUD$ 1375 Ex GST

We want you to have the best gear! Trade in your old version 3 system for a shiny new Power Tool 5. Supply your own iOS device or ask us to quote you on an iPad or iTouch.

Version 2 GymAware Sensor Trade In – AUD$ 1575 Ex GST

Yes. We are even offering a trade in on our oldest GymAware units! We believe in long term customer service. Send in your old units and we will get you right back on the cutting edge with Power Tool 5.

Why Upgrade?

All good things must come to an end. All our older systems require particular Palm OS devices to run. Since these are no longer made or supported, we can no longer offer support for these units. Also the old GymSync process is becoming unreliable due to compatibility issues with modern operating systems.

The good news is that the new units are even easier to use, more accurate, and come with more features.

It really is time to upgrade! 

Email us now to organise your upgrade.

What Version Do I have?

Not sure what version you have? Check out our identification guide here. Or just call us!

There are lot of Android users, who still use GymAware.  The best way to look at it is that the iPod is just an integral part of the kit and is only used for that purpose, so in that sense the OS is a non issue. A lot of people already have an iPod or iPad so the devices are not included as standard. And then there is the growing choice of iOS devices to choose from.

We also advise against using iPhones with the system even though they are 100% compatible. The last thing you want is a phone call interrupting a testing session with a client, and you don’t want to be lending your phone to staff or clients to do self testing.  So whether your Phone is an iPhone or an Android based phone, we still recommend getting one to the “non-phone” iOS devices to keep with the kit or in the gym.

We understand your desire to use an Android (or Windows) ecosystem but for us the diversity of android devices and its lack of a consistent small medium and large (iPod/iPad mini/iPad) option that works for all variants of the OS make it very unlikely that we will be porting to android until this changes. The rigid controls built into the Apple development process, though often very frustrating to work with, ensure that users get a very easy and consistent user experience across the whole range of tablets.

In summary your decision of whether or not to go with GymAware should not be based solely on the platform of the device, but more on whether or not GymAware will give you a competitive advantage; our experience with clients is that it will.

In Brendyn Appleby’s recent article on asymmetry he explained the value of comparing the performance of different limbs with GymAware.

Here is an extra tip for comparing data sets.

In the GymAware Online web app, when you drill down into your data sets, you can select multiple sets done on the same day to graph against each other.

Here we are comparing two different types of squat jump, but it could just as easily be left and right leg press (provided you recorded them separately)

And the result looks like this.

Pretty neat!

Rehabilitation and Injury Reduction

By Brendyn Appleby
Assistant S&C Coach, Emirates Western Force
ASCA Level 3 Master Coach

Many of the reporting strategies I have mentioned previously have encouraged athlete use of the GymAware for immediate motivation, and enabled medium- to long-term athlete tracking and program assessment. In this article, I would like to present a few strategies that may assist with specific injury rehabilitation, injury reduction through the identification of asymmetry. For these reasons, the use of the GymAware for identifying and reducing asymmetry is possibly the most encouraging aspect for the athletes.

I use GymAware in single leg exercises such as leg curl, single-leg leg press or step-ups to assess bilateral asymmetry

What is an asymmetry?

Lower body asymmetry has been examined in several ways within the literature and strength and conditioning professionals are generally concerned with any is a difference in output between the right and left legs. The most commonly reported methods to investigate lower limb asymmetry have been jumping and hopping, either vertical jumping or horizontal [2, 4, 5]. Isokinetic methods are also common, but often not easily accessible [1].

Although it is widely acknowledged that the presence of bilateral asymmetry (a discrepancy in measureable performance between left and right limbs, either in centimetres jumped vertically or horizontally, or force or power output as measured by gym based or laboratory based exercise tests) in elite athletes is undesirable and recognised as a precursor to injury, the literature is yet to provide a conclusive figure on what represents imbalance and several studies have cited 10-15% as an observed range in athletes [3, 4].

For further information, I would suggest the following references:

• Hewit, J., Cronin, J. and Hume, P. Multidirectional leg asymmetry assessment in sport. Strength and Conditioning Journal. ahead of print – 2012.
• Newton, R.U., Gerber, A., Nimphius, S., Shim, J.K., Doan, B.K., Robertson, M., Pearson, D.R., Craig, B.W., Hakkinen, K. and Kraemer, W. Determination of Functional Strength Imbalance of the Lower Extremities. Journal of Strength and Conditioning Research. 20: 971-977. 2006.

Identifying Asymmetry?

I use GymAware in single leg exercises such as leg curl, single-leg leg press or step-ups to assess bilateral asymmetry. Practically in the gym, when performing a unilateral exercise, it is not ideal to have an athlete perform reps on one leg, wait to change the GymAware selection to the other side (right or left) and then continue. Therefore, when I am working with my athletes, I ask them to complete all of the prescribed reps (for example, 3 on each side) on the right side, and then all the reps on their left. I then know that the first half of the set (reps 1 to 3) is the right side and the second half (reps 4 to 6) is the left. The outcome is a graph such as Figure 1. In Figure 2 the graph is of an athlete who demonstrates a limb dominance as opposed to an imbalance due to injury. Nonetheless, this would require further assessment and intervention.

Editors note. You can also compare selected sets directly on the online application. 

Fig 1. When working with my athletes, I ask them to complete all of the prescribed reps (for example, 3 on each side) on the right side, and then all the reps on their left

Fig 2. This graph is of an athlete who demonstrates a limb dominance as opposed to an imbalance due to injury

Previously these graphs used to be created after the session on the GymAware website. Now with the new iTouch apps, you can create a similar graph immediately on the gym floor and provide this sort of feedback to your athletes. I have found another useful function is the “Percentage of Best” which is a variable that can be selected to show real-time results. Although all reps are calculated based on the first rep, all I want to see is that the difference between their left and right is within the commonly referred to 10% figure. One set outside this range may be due to technique or effort, but if it is consistently outside this range, a more thorough analysis is required. What is excellent about this function, is that after a few trials and working with the athlete, they quickly understand the process and can monitor it themselves during the session.

As the coach, I am able to then continue coaching the entire group (10-30 players depending on the session) and can review the performance later and make changes to the program for the next session. Whether that involves additional repetitions, sets, or supplementary exercises depends on the specific circumstances. For feedback, whether you use the graph or percentage function may depend on which form your athlete understands best – do they decipher pictures better than numbers? All athletes are different so I try both and see which they respond to best.

A more thorough analysis

With consistent imbalance, or athletes returning from a significant lower body injury that has affected their lower body training for several months, I assess  each limb more thoroughly. I have found that within a short time frame, an athlete returning from long-term injury can regain a reasonably balanced strength level (as measured by a repetition maximum test). However, it has been interesting to observe the load-power curve of each leg independently as they can be different between the previously injured leg and non-injured leg. This can be seen in Figure 3. Here, the athlete is able to lift the same external load with their left and right legs. However, you can see that the power produced by each leg is very different. I have added error bars at 5% to show the magnitude of the difference. Although the error bars are not entirely precise (but it gives an indication), if the bars do not overlap, then there is roughly a 10% difference between limbs and requires attention.

These forms of analysis require a bit more time than the previous styles of analysis I have mentioned in earlier articles, but I believe them to be very important. Also, these are only produced for those athletes identified, which may be between 10 to 20% of a squad.

Here, the athlete is able to lift the same external load with their left and right legs. However, you can see that the power produced by each leg is very different.

Training to improve Asymmetry.

From my experience, the first step in overcoming asymmetry is to identify it. This may sound rather unsophisticated, but using this form of feedback with athletes can have a profound effect on reducing asymmetry. In many cases, maximum strength has not been the issue, but rather the ability to move a given load with similar effort, or velocity, between sides. Therefore, training at submaximal loads, mindful of the target, has been a relatively successful strategy to date.

There are many possible reasons for the presence of asymmetry which require thorough investigation. In close consultation with the medical team I work with, a frequent strategy (amongst others) has been to slowly bridge the gap in imbalance starting from a position of balance. When training athletes with asymmetry, we are essentially trying to bring the lines on the graph closer together. We start at the point of divergence (where the error bars no longer meet, in this example, 100kg) and that is our maximum load and we train with the range of loads up to this maximum until the gap closes. Once that is achieved, we can increase the load and work on closing the next gap in the curve.

Conclusion

As stated, I have primarily used this strategy to assess imbalance with single limb performance in leg press and step-ups. I have used it sometimes for other areas such as leg curl for left and right hamstring imbalance. It could be further applied to upper body exercises such as latpulldown or a cable chest press perhaps, if these were important areas of imbalance for upper body dominant sports such as water polo or swimming. The main points for using a GymAware in this area is to regularly monitor your athletes, have a process to be able to further analyse any asymmetry and put in place strategies to rectify the imbalance. Part of your strategy should involve collaboration with peers as overcoming symmetry may be multi-factorial. Identifying and overcoming any imbalances is a very encouraging training process for athletes and a very rewarding one.  Hopefully you find some of this information useful for your athletes.

For more articles from Brendyn Appleby go here.

References

1. Croisier, J.-L., Forthomme, B., Namurios, M-H, Vanderthommen, M. and Crielaard, J-M. Hamstring Muscle Strain Recurrence and Strength Performance Disorders.The American Journal of Sports Medicine. 30: 199 – 203. 2002.

2. Hewit, J., Cronin, J. and Hume, P. Multidirectional leg asymmetry assessment in sport.Strength and Conditioning Journal. ahead of print – update. 2012.

3. Hoffman, J.R., Ratamess, N.A., Klatt, M., Faigenbaum, A.D. and Kang, J. Do Bilateral Power Deficits Influence Direction-Specific Movement Patterns? Research in Sports Medicine. 15: 125-132. 2007.

4. Maulder, P., and Cronin, J. Horizontal and vertical jump assessment: reliability, symmetry, discriminative and predictive ability.Physical Therapy in Sport. 6: 74-82. 2005.

5. Newton, R.U., Gerber, A., Nimphius, S., Shim, J.K., Doan, B.K., Robertson, M., Pearson, D.R., Craig, B.W., Hakkinen, K. and Kraemer, W. Determination of Functional Strength Imbalance of the Lower Extremities.Journal of Strength and Conditioning Research. 20: 971-977. 2006.

Would you like $100 off the price of a new GymAware Kit?

We have made it even easier to by GymAware now with the Kinetic online shop, and as an opening special we are offering $100 off for newsletter and blog readers.

To get this discount all you need to do is enter this code  N76H892O5V when you check out.

The offer is exclusive to newsletter and blog readers so feel free to forward this to a colleague or Tweet it!

Offer expires Oct 9th 2012, Dont miss it!