Are isometrics in your toolbox?

This post looks at using isometric muscle contractions as an integral ingredient to your strength and conditioning programme, rehabilitation programme or even as part of your warm-up routine using research to help understand the effectiveness of this type of training method.

There are two types of muscle contractions, isometric and isotonic. Isotonic refers to the muscle force being produced with a change in muscle length. There are two types of isotonic contractions, concentric (muscle length decreases) and eccentric(muscle length increases). The term isometric derives from the Greek word meaning ‘of the same measure’ and basically refers to a muscle contraction with no change in muscle length i.e. holding an object in a static position.

A large percentage of runners still continue to use static stretching as part of their warm-up routine to help increase their performance and /or reduce injury which is concerning since studies by Che-Hsiu et al. (2018), Herbert et al. (2011) and Nelson et al. (2005) have all demonstrated in their research that static stretching has little to no impact in preventing soreness after exercises but furthermore may impact performance and rate of injury in an undesirable way with Pojskić et al. (2015) suggesting that the more active, dynamic warm-up being the preferred choice for injury prevention and increasing performance.

But static stretching does have a place in a runner’s toolbox and when used in conjunction with some isometric holds, could provide a runner with a time-effective way of improving strength or correcting a specific muscle imbalance that can lead to muscle soreness or injury. Makaruk et al. (2010) report that post-exercise static stretching is effective in helping to correct these muscle imbalances and help with increasing a person’s range of movement.

Every runner’s dread is becoming injured particularly when confidence is high and you are moving well. It affects the consistency of training, it impacts mood and interrupts the flow of working towards a desired goal. In 2021, Ullman et al. stated that isometric exercises with the combination of a dynamic style warm-up is a more effective way to decrease injury rates as the isometric feature is hypothesized to increase the post-activation potential of specific muscle groups i.e. get them firing! Widodo and colleagues (2022) similarly described the use of the isometric’s ability to improve the muscle’s ability to resist force under any condition. For a runner, every muscle group below the hip would benefit from this, particularly the soleus and gastrocnemius and let us not forget the tendons associated with these namely the Achilles and peroneals. Widodo (2022) studied the impact of isometric interventions on the hamstrings and elaborated on the lack of strength as the main cause of injury.

Now let’s not forget the use of isotonic contractions (concentric and eccentric) as these also have a place in the runner’s toolbox and are equally as effective in different ways. A study by Wasielewski and Kotsko (2007) looked at the effectiveness of eccentric contractions in treating tendinopathies in the lower limbs and concluded that eccentric exercises may produce better outcomes than other therapeutic treatments as also supported by studies from Alfredson et al. (1998) and Van Der Pla et al. (2011). Kanniappen and Sathosh (2020) also suggested that isometric exercises help reduce tendon pain, increase recovery and reduce the likelihood of the injury reoccurring again, particularly for people suffering from patellar Tendinopathies and so it seems that applying load to a tendon and muscle can also have some rehabilitation benefits, performance enhancing and strength and conditioning benefits.

Moore (2020) summarises the advantages of using isometrics and eccentric contraction types brilliantly. The specific application to a targetted muscle group and the lack of movement means that if injured the athletes will experience lesser pain at the injury site than if a concentric or eccentric exercise was applied. Another benefit of using isometrics is if you are experiencing a training plateau when trying to increase strength. This example was given.

“For example, we tend to be weaker at our end ranges of motion. Think about a heavy back squat for example: pushing the weight up from the very bottom, or the “hole” is typically where most folks struggle. But sitting in the bottom of your squat with a weighted barbell on your back can help you develop the strength you need to stand the weight back up. The same concept applies to push-ups or bench press. Holding your body an inch or two above the ground during a push-up will help make the entire movement easier. What this does is place more of a focused emphasis on the muscle, helping to boost muscle growth.”

 

When using eccentrics, the elongation of the muscle fibres causes micro-tears, more so than a concentric contraction and may mean a longer recovery process is required between training sessions. As the body repairs and adapts to the eccentric training, muscle fibres get stronger and are effective in stimulating hypertrophy (muscle growth). For runners, one of the most effective uses of eccentric training comes in the form of increased tendon and ligament strength which ultimately helps reduce the risk of injury.

And finally, concentric contractions help develop strength. Whilst concentric contractions do not cause as many micro-tears as eccentric training, it is still effective in resisting fatigue, and developing power and strength and should not be dismissed. Similarily to running training, you have to put the body in this case the muscles under stress (mirco-tears) in order for the body to physiologically respond to the given stimulus. Think supercompensation curve!

Top 10 Benefits of using isometrics (ASFA)

1 – Improves strength, stability and endurance

2 – Improves posture

3 – Reduces risk of injury

4 – Increased strength

5 – Increased power

6 – Increased speed

7 – Increase lean muscle mass

8 – Improved coordination and balance

9 – Increased bone density

10 – Increased metabolism

And finally – after having done these over the last 2 months → Minimal time is required for a big impact!

Isometric Toolbox

So here are my go-to isometric exercises used before or after training. Note that whilst there is less movement, you may think less mirco-tears, the fact is force is still being generated to maintain your posture, balance, and body position and as such the muscles that are being recruited are working. You will feel the burn!!!

Aim for 3 x 1min each leg, then build progressively (3 x 1min / 3 x 1.30min / 3 x 2mietc etc) Aim for 2-3 times per week.

Here are my top 5 Isos

1 – Plank

2 – Wall Sit

3 – Split Squat / Lunge

4 – Glute Bridge

5 – Calf Raise (Straight knee for gastrocnemius / Bent knee for soleus)