The occurrence of hamstring injuries often comes down to a series of contributing factors - some more significant than others - which eventually lead to muscle tear. This can include the footballers general flexibility, poor strength or range of motion in the hamstrings, or a muscular imbalance in other areas which can increase the workload on them.
Who is susceptible and why?
For speed players, hamstring injuries will always be more likely to occur, this would mean centre forwards (the most susceptible position), wingers and full backs (and possibly your box-to-box midfielders who are reliant on their pace eg. Yaya Toure, Jordan Henderson). Frequent sprinting, jumping and tackling with weak or tight hamstrings is likely to eventually force them into submission, and result in a grade 1 (small strain - 2-3 weeks), grade 2 (partial tear - 6 weeks) or grade 3 (full rupture - 3 months).
How can we prevent this?
Warm Up: Sounds obvious right? It is staggering how many amateur footballers can fail to get past the first hurdle of a successful performance by skipping or neglecting the warm up. This is the quickest route to a hamstring injury if the blood isn’t flowing in this muscle group. Ensure that you have carried out some jogging at progressed intensities, dynamic stretches, and sharp changes in direction with and without the ball. 10 second ‘preparatory’ stretches can also be held for all muscle groups, before carrying out some more ball manipulation or opposed play pre-kick off.
Stretching: Don’t just stretch for games, you can massively decrease your chances of injury by stretching on a daily basis. Footballers at Bournemouth University (2012) were able to increase their hamstring range of motion by an average of 20 degrees in 4 weeks (using the 90 degree hip flexion test), just by carrying out a 10 minute stretch routine twice a day and five days a week along with massage and SMR (see below).
Strengthening: Carry out an exercise programme that includes movements like lunges, romanian deadlifts, and swiss ball leg curls. These build strength in the hamstrings across the hip and knee joints, and will lead to greater stability, power and endurance for the footballer as the season goes on.
Massage and SMR: Before you leave for football, grab some baby oil/grapeseed oil and give you legs a quick and vigorous rub down, with particular focus on the hamstrings. After a game, you (or better, someone else) can massage your hamstrings again, going deeper into the tissues this time to reduce the tension in the damaged muscle fibres. You can also carry out self myofascial release with a foam roller (they only cost 10-20 pounds) on the major muscle groups and illiotibial band to keep you loose and injury free for the next game.