So we've come to end of the week and I've rounded it off by a brutal legs session... Lovely!!
However whilst I cool down and catch my breath, it gives me a chance to pass over some of my tips for strengthening and developing the hamstrings, as I find people lack the knowledge and understanding of proper exercise selection and repetition ranges when it comes to gaining mass and size of the hamstrings.
Now before I begin it's important we understand the function and anatomy of the hamstrings.
Comprised of three heads - semimembranosus, semitendinosus and the bicep fermoris, the hamstring serves both as a knee flexor and hip extensor.
Predominately comprised of fast twitch muscle fibres, the hamstrings servers a large role in explosive power movements, such as sprinting and jumping.
When training the hamstrings it's important to take note of two things...
1) When the hamstrings are trained as a HIP EXTENSOR, so such exercises as - Romanian Deadlifts (RDL's), Good Mornings, Hyper Extensions etc, the make up of the fibre type is predominately slower twitch, Meaning a higher rep range favor these movements better. i.e 8-15 reps. 
2) When the hamstrings are trained as a KNEE FLEXOR, such as lying leg curls, standing leg curls, Glute Ham Raises (GHD's) etc, the fibre type is predominately fast twitch so a rep range of 1-6 reps would suit better and of an explosive nature. 
Reasons for this is when flexing at the knee more of the bicep femoris is recruited which is higher in fast twitch muscle fibres compared to the semimembranosus, and semitendinosus which are slower twitch and recruited more when it comes to flexion/extension of the hip.
So where does this leave us when it comes to exercise selection?
Researchers at the University of Memphis published a paper in the June edition of the Journal of Strength and Conditioning Research.  The researchers got 12 well-trained strength athletes to do four exercises for the hamstrings on different occasions: the Romanian deadlift, lying leg curl, good morning and the glute ham raise.
The researchers used electrodes to measure the electrical activity in the muscle groups, an indicator of how hard the muscles had to work during the concentric and eccentric movements.
Here are their findings:
When it came to recruitment of the bicep femoris - Romanian deadlift came top for both eccentric and concentric strengthening (lying leg curl was the least effective exercise) .
For the semitendinosus and the semimembranosus, the Romanian deadlift was the best exercise for the eccentric movement. However for the concentric movement the glute ham raise was shown to be the best .
The researchers of the study concluded, athletes wishing to strengthen and develop their hamstrings should look at prioritising RDL and glute ham raises in their program.
We here at Hall Training Systems always like to ‘mix it up’ and like to put our clients through progressions on exercise as well as a change in rep range, sets and tempos every few weeks or so. However one exercise that’s normally at the core of our programs is a variation of the deadlift, be it - deadlift, trap bar deadlift, snatch grip deadlift, single leg deadlift or Romanian deadlift!
 PICP Level 2- Rhode Island
 McAllister MJ, Hammond KG, Schilling BK, Ferreria LC, Reed JP, Weiss LW. Muscle activation during various hamstring exercises. J Strength Cond Res. 2014;28(6):1573-80. doi: 10.1519/JSC.0000000000000302.
About Chris Hall
As the founder of Hall Training Systems, it is my mission to provide you with the very best personal training experience. I set up Hall Training Systems as Oxford's leading personal training service in nutrition, performance and weight loss, ensuring I can deliver the very best in training techniques.
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