1. What is strength training? 
2. What are the principles of strength training? 
3. What are the benefits of strength training? 
4. Misconceptions of strength training 
5. How often should you strength train? 
6. Common strength training equipment 
7. Strength training vs cardio 
8. Does strength training burn calories?
9. Strength training examples
10. Conclusion 
11. References 

What is Strength Training? 

The term strength, or strength training, is often used interchangeably with resistance training or resistance exercises. Strength or muscular strength is defined as the ability to generate maximum external force. (1) An internal force would constitute part of the human body applying force on another part whereas external forces pertain to an environmental force against the human body. Therefore, for this article, the definition of strength relates purely to how the human body can exert force against an external factor. Other definitions relating to strength describe it as the ability to contribute to maximal human efforts in sport and physical activity (2). Regardless of the exact definition used, strength is fundamental to a human being outside of the realm of just sports performance context. Joyce and Lewindon (2014) go on to further define maximal strength as the ability to apply maximal levels of force or strength irrespective of time constraints and relative strength is the ability to apply high levels of force relative to the athlete’s body mass (3).

Strength can be distinguished based on three muscle actions: concentric, isometric, and eccentric contractions. Concentric actions refer to the muscle shortening, and normally maximal strength is measured concentrically before an eccentric movement occurs. Eccentric action is the opposite of concentric in that a muscle creates less tension and lengthens. Isometric contractions almost sit in between concentric and eccentric in that they create tension without shortening or lengthening (4). 

Figure 1 shows an example of the bicep muscle and how each part of a bicep curl will pertain to the type of action being used. As the individual curls the weight towards their body, they are moving it concentrically where the bicep muscle is shortening. As soon as the weight starts to move away from the body, the bicep muscle is lengthening and therefore is the eccentric part of the exercise.

Figure 1. – Muscle can actively exert force regardless of whether the muscle gets shorter, stays the same length, or gets longer due to the opposing force (20).

Strength can often be termed as ‘absolute strength’ or ‘relative strength’. Absolute strength pertains to an athlete’s capacity to exert maximum force regardless of what their body weight is (4), whereas relative strength considers the body weight of an individual and therefore is a ratio of the two. Some sports are divided into various weight categories such as boxing or gymnastics, in which case a high level of relative strength is imperative. 

Finally, general strength training looks at the foundation as an entirety of improving the strength of the entire body. Low general strength levels may indicate or lead to injury or a higher susceptibility of it, or asymmetrical issues and imbalances. Specific strength training takes a more sport-specific approach so athletes can be strong in certain planes, ranges of motions or movements based on the demands of the sport (4).

What are the principles of strength training?

Constructing a strength plan and goals requires us to understand the basic principles to make sure we are getting the biggest bang for our buck. The same goes for aerobic training, these foundational principles are specificity, overload, and progression. 

Specificity is a basic concept where an individual is to train in a specific manner to produce a specific response or action. In practical terms, if someone wanted to design a program around strengthening their hamstring muscles, they would have specific exercises to match the required demands. Exercises that could occur in this scenario may be the deadlift, glute bridges, or Nordic curls. In an athlete’s sense, specificity can relate directly to the sport by mimicking movement patterns or becoming a supplementary addition to improve strength levels that can transition to the pitch and aim to enhance performance.  

Overload is about assigning training or sessions of greater intensity than the athlete is accustomed to. Without the stimulus overload, even a well-designed program will limit the athlete’s ability to seek improvement (2). An example of progressive overload can be changing the load a person is lifting to make it harder or adding in more strength days per week. Another manipulation could be made by adding more exercises to the session or tweaking the rest periods in between. Finding the balance between overloading and not overtraining is vital. If a program is correctly designed, it will challenge the individual enough to enhance strength improvements but consider required recovery/rest days.  

Progression has a methodical approach to prevent potential overuse or injury from occurring. It may seem like you can make a big leap by lifting a heavy load one week compared to the last, but jumping straight into it without a designated plan can have many disadvantages, with injury being at the forefront. Lifting heavy loads will provide an important overload, but not at the expense of sacrificing proper technique and form. Progression should, when applied correctly promote long-term training benefits (2). 

What are the Benefits of Strength Training?

Strength training provides a wide range of benefits to individuals regardless of age or experience level. It has been shown to increase muscle size and strength, help stabilise joints and ligaments, improve neurological signalling, aid in power mechanism and speed as well as many studies detailing the importance it can provide for mental health. Research has shown that doing strength training can reduce symptoms of various chronic diseases like arthritis, depression, type-2 diabetes, osteoporosis, sleep disorders and heart disease. In addition, some research demonstrates that strength training in older adults with functional limitations can reduce falls (5, 6). A long-term study conducted by Nelson et al. noted that women aged 50-70 years old who participated in strength training twice a week for one year became stronger, increased their muscle mass, improved their balance, and reported better bone density in comparison to the control group who did no strength training at all (6). 

Misconceptions of Strength Training?

A few studies have investigated the preconception of strength training about males’ and females’ perceived importance of it. A common belief today is that many females have a negative preconception of strength training for multiple reasons. Some believe that by engaging in strength training they will add a lot of muscle mass and become aesthetically bigger, while others believe that is it not necessarily important for them to participate in whether they are an athlete or not. Poiss et al (2004) surveyed this exact issue at the collegiate level by exploring the perceived rates of the importance of strength training and found that male athletes were found to be significantly more likely to consider weight training as essential to their sport-specific training than females (8). Similarly, Bennie et al (2020) completed a comprehensive study, spanning 28 countries in Europe and found that 19.8% of men participated in strength training activities ≥2 times a week compared with 15% of women (9). 

A common misconception is that cardio-based training is the best and only way to lose weight or specifically, body fat percentage, and strength training does not do this. Excessive body fat can be associated with a major risk for general health and can lead to life-threatening conditions or diseases. Several studies (11, 12, 13) have found that increasing resistance or strength training can positively affect body fat percentage alongside managing obesity or metabolic disorders (12). In line with these findings, a study that compared endurance to strength training over 10 weeks in male physically active participants, concluded that although resistance training alone may improve muscular strength and basal metabolic rate (BMR), and endurance training alone will increase aerobic power and decrease body fat percentage, a combined approach is optimal (10). 

NB! An important thing to note is that muscle has a higher density than fat. If an individual implements strength training into their routine they could find an increase in weight (kg) however their fat stores have decreased, leading to reduced limb circumference and a change in body composition. Checking body fat percentage is a better metric that a person may look to improve. To summarise, a bodybuilder and an individual with obesity could have the same BMI, but the bodybuilder would have a higher percentage of muscle mass than the individual with obesity, who will have a greater percentage of body fat.

How often should you strength train?

The amount of strength training required will depend ultimately on the goals. An athlete looking to focus on maximising strength to translate to their sport will have different goals compared to an athlete or individual who is returning from a serious injury and focusing on regaining baseline strength. An elderly person looking to keep a good foundation of strength to help with functional movement will have different goals than a bodybuilder looking to enhance hypertrophy. These different scenarios will elicit a different training need and therefore frequency, duration, and load needed. 

Various research alludes to differences in the frequency of strength training that should take place each week. Outside of sports performance, literature and article results can fluctuate from anywhere between 1-4 sessions per week as a general recommendation. Many studies will look at untrained, non-elite or recreational adults who engage in resistance training and often conclude direct strength improvements. In terms of experienced lifters, Lasevicius et al (2019) examined the difference in resistance-trained men by comparing 2 sessions a week to 3 sessions to determine if any significant differences were noted. The study concluded that although a significant difference was found between pre and post-test scores, there were no differences between the two groups and despite 2 or 3 training days per week, they both evoked similar responses (18). Contrastingly, other studies have found differences between groups when comparing 3 strength sessions a week to 6 sessions concerning the training volume per session (19). What does this mean? There is no exact science with how much strength training you should do as it will elicit various physiological responses for individuals at different time points. Strength training provides major benefits to health, so just getting started and remembering individualisation is key. 

Strength Training for Athletes 

There are multiple ways that strength training can be programmed, often, athletes will fall into a periodization model where it considers their competition fixtures throughout the season and looks to maximise strength at the right time. There are multiple tactics to do this, but with periodisation, a coach can manipulate loads based on the goals within a set cycle. An annual plan is usually put together at the start of a new season which incorporates the macro-cycle which is essentially looking at the bigger picture. What games are there, and how long is the pre-season, in-season, and off-season period in terms of weeks. Within the macrocycle, this is then broken down into a meso-cycle and then finally a micro-cycle. The micro-cycle is a short time that could equate to a week as an example, which provides details of how the exact strength sessions may look in terms of exercises, reps, sets etc. The meso-cycle sits in between both which looks at when strength training sessions may be added throughout the month with a potential focus attached to it. 

Figure 2. shows an example that Suchomel et al (2018) documented on periodisation with the various stages. The preparatory phase is typically the off-season where maximal strength can be focused on then as pre-season begins this will start to transition to strength-power training. During the season most sports will strip back on strength and replace it with technical or tactical training. Strength-power is imperative for the athletes to complete during the main season to keep them strong and ticking over.   The only difference is the load may be reduced and the session will be scheduled by the S&C team to promote enough recovery time before competitive games to avoid a decrease in performance. 

Figure 2.  An example of strength focuses during the preparatory and competitive phase (7). 

Common Strength Training Equipment

Strength training can be completed with various equipment or methods to stimulate a similar response. Examples include free weights, body weight movements, machines, and/or resistance/elastic bands. 

Bodyweight exercises

For a beginner, body-weight exercises are a great way to learn different movements and perfect form. A completely new beginner will likely find adaption through body-weight exercises as they have several advantages as noted above in the benefits of strength training. Not only do they target various muscle groups but there is the potential for lots of versatility. A plateau can occur when using strictly body weight exercises as an overload of a stimulus is limited in nature so other strength training methods are often added or advised to seek further improvement (6). These exercises or movements are great for people returning from injury or starting an activity for the first time. It is the foundation or building blocks to get people moving correctly before adding additional load. 

Free Weights

Dumbbells, kettlebells, or barbells can be used as free weights and as the name suggests, they are not attached to a machine. There are many advantages to using free weights and lots of exercises that can be progressed or regressed as necessary with them too. One main advantage is that by using free weights they force stabilisation, range of motion, and coordination. A back squat for example using a barbell will require a person to work their quadriceps in the concentric movement but they need to engage other muscles and the core to create the movement to be as efficient and smooth as possible. With free weights, an element of balance is needed so alongside strength gains these types of exercises can help improve balance and coordination as well.

Machines

Many different machines can be found in a gym setting that looks to isolate specific sets of muscle(s). For a beginner, machine exercises may be a great place to start as they are often user-friendly, and less technique is required in comparison to free weights. They provide isolated work and load to a specific area of the body which means any discrepancies or imbalances could be addressed by adding in machine movement. If imbalances are a problem, machines can become a potential hindrance if one muscle group or one side dominates or takes most of the force. For example, a leg press machine requires both feet to push against the resistance. If an individual has an obvious stronger side, they may find that one leg is working harder than the other, therefore, taking most of the weight. A recommendation would be to assess any potential imbalances or discrepancies an individual or athlete has before assigning a program as exercise selection can be manipulated. Machines could still be used if other exercises address the imbalances that were found. Often, a machine has less risk of getting the movement wrong and can move the body through the desired range of motion.

Read this article to find out more about free weights vs machines. 

Resistance Bands 

Resistance bands can be used to create tension or make movements more difficult as the muscles work to resist the pressure created. Resistance bands can come in all shapes and sizes with the strength of the band getting thicker which ultimately means it is harder to resist. Beginners can use bands as a good starting point and work their way up to harder bands as they become used to the tension. They are a great way for injured athletes to build up strength after rehabilitating from a knee ligament injury (14). One disadvantage to using resistance bands is it is hard to evoke the same resistance each time as it is purely subjective.

Strength Training vs Cardio

On a basic level, strength and cardio training play different roles, and have an obvious difference in that cardio training aims to improve oxygen efficiency whereas strength training adds stress to the muscle to gain strength. Going for a steady state long run versus completing heavy weight lifts in the gym will provoke different energy pathway responses. 

Our energy pathways will work together but depending on the activity we are doing, will depend on which energy system is working as the predominant source. Maximal strength, often, is where minimum reps are conducted but the load is extremely high. An example of this may be an athlete completing a 1 repetition maximum (RM) – 3 RM bench press. It is an intense few seconds of work where the body is heavily relying on the adenosine triphosphate-phosphocreatine (ATP-PCr) system to provide a high capacity of power through the stored ATP and PCr we have but it will only last a few seconds. Once this energy has been used, our body will then upregulate the anaerobic glycolysis which provides more energy, still at a high-power outlet, but not the same as the ATP-PCr. The benefit to the anaerobic glycolysis is the duration can be longer which will certainly help when we look to do strength training where it lasts more than a few seconds. In terms of cardio-based training, again, it will depend on the intensity and duration of the task to what energy system is in the driving seat. If a person were to do a long steady state run at the same speed, they would be utilising their aerobic capacity system as their predominant energy system. This will allow an individual to be able to work for a long period at a relatively low intensity. Even by utilising anaerobic energy pathway, we often rely on strong aerobic power for a quick recovery and regeneration between actions (15) 

Does Strength Training Burn Calories?

Having already established that strength training can have profound effects on an individual’s health it is important to note how strength training can and does burn calories. It is often associated that aerobic-based activities are the most effective for burning calories and improving cardiovascular fitness. By participating in regular muscle-building activities, the muscles are metabolically active and will therefore burn calories (16). Muscles require a lot of calories to function even at rest and strength training requires substantially more calories. With regular strength training, muscle mass will increase which increases your metabolism and therefore can lead to burning more calories at rest and throughout the day (17). 

Strength Training Examples. 

Strength training sessions will differ depending on your desired goal or outcome. The force-velocity curve in Figure 3 is based on your 1RM and the percentage you are working at. Working at the top of the y-axis shows that the weight is very heavy and maximal strength is the main goal whereas the furthest point along the x-axis has no more than 30% of your 1RM where you are focused on moving it quicker, but the load of course is lighter.

Figure 3. Force Velocity Curve.

A strength session can be a total body focus which encompasses movements accommodating a variety of muscle groups from both upper and lower. Some like to do a split, where they complete an upper-body session one day and a lower-body session the next. Another well-known spilt is something called the ‘push and pull’. An example of a push exercise is where the movement or weight is being pushed away from the body, such as a bench press, push-up, shoulder press or overhead press. As the word ‘pull’ insinuates the body is contracting muscles and pulling a force towards the body. Examples of a pull exercise could be pull-ups, lat pull down, bent-over rows or a deadlift. An example for a beginner is represented in Table 1 and specifically for a female football athlete in Table 2. These are noted as generic examples of how a strength session could look, but individuality must be considered when designing a programme to suit the needs, goals and preferences of the individual. 

Table 1. An example of a total body strength session for a beginner. 

*The individual will need to have a play around with a weight that they know they can get to around 12-15 reps but does not inhibit them reaching the desired amount, or it is not easy enough they can progress over 15 reps. 

Table 2. An example of a total body strength session for a female football athlete in the off-season during the summertime.

As an athlete, coach or practitioner interested in more specific elite athlete training, check out the article on training methods of elite-athletes.

Conclusion 

Strength usually refers to our ability to resist an external force and much literature urges the importance of regular strength training. It has been shown to increase muscle mass, provide stability to ligaments and joints, develop stronger bones, and help reduce the potential of various illnesses and diseases. There are multiple ways to engage in strength training exercises through machines, free weights, resistance bands or bodyweight movements. Strength training is imperative for everyone, not just athletes, and will help enhance overall quality of life with a regular structured routine.

The post Strength Training appeared first on Science for Sport.

1. Summary
2. History of Women’s Football 
3. Needs Analysis of the Female Footballer
4. Considerations for Women’s Football
5. Data Analysis in Women’s Football
6. Performance Testing in Women’s Football
7. Program Design Ideas for Women Footballers
8. Conclusion 
9. References 

Summary

The demands of women’s football are ever-evolving. Like all sports, it is a process of identifying the key physiological metrics and demands that are placed on the athletes to further enhance performance across various levels. 

History of Women’s Football

For 50 years, women were banned from playing football. During the first world war, the men would have fulfilled their duties of fighting in the war, while the women stayed at home to reoccupy the roles that were left, working in factories, and assisting to raise funds for the war efforts. During this time, women took up playing football in more organized games and events with an estimated 150 teams created across the country. 

After the First World War, the men’s leagues which were previously suspended, resumed, despite women’s football being at an all-time high where a match on Boxing Day drew in a crowd of 53,000 people. In 1921 the English FA decided to ban women’s football quoting it to be, ‘quite unsuitable for females and ought not to be encouraged’. The ban was later lifted in 1971, ending a 50-year absence of women’s football. (1)

Women’s football is now at an all-time high with more global exposure, greater access, and massive demand for more resources at both elite and non-elite levels. Just six days into the FIFA Women’s World Cup 2023 a record high of 1.5 million tickets were sold (2). Coming off a historical UEFA Euros campaign for the Lionesses, it was more than just bringing home a trophy – it was creating a lasting legacy.

Looking to the future, the Lionesses wasted no time in creating a UEFA-supported legacy programme to get more females into football consistently. The history of the game is pivotal in understanding the demands as it has changed and will continue to change through time. 

Needs Analysis of the Female Footballer

It is imperative as a practitioner to complete a thorough Needs Analysis to not only identify the demands an athlete has placed upon them in a game scenario but to inform the training strategies while aiming to minimize any potential injury threat.

Focusing on strictly women’s football, Turner and colleagues (2017) produced an in-depth ‘Part 1 – Needs Analysis’ of the game looking at these key areas. A follow-up piece was created, noted as ‘Part 2 – Training Considerations and Recommendations’. This research is an important starting point to understand the key demands of the game.

In basic terms, during a game, a female footballer is likely to: 

• Sprint 
• Jog 
• Walk 
• Sideways or lateral shuffle 
• Backwards running 
• Jockey 
• Jump 
• Turn or change of direction 

Energy Systems 

The movements identified correspond with our energy systems depending on the demand placed on each activity listed, and the time and intensity those movements are completed for. In simple terms, the energy systems are broken into aerobic and anaerobic metabolism where oxygen is either present or not, respectively. 

The anaerobic energy system is divided into alactic and lactic components, which ultimately refers to a process of spitting stored phosphagens, ATP and phosphocreatine (PCr), and the nonaerobic breakdown of carbohydrates to lactic acid through glycolysis (3). The aerobic system, also known as the oxidative system, requires oxygen to produce ATP and is the preferred system for long-duration and/or low-intensity activities. All three energy systems will be active during exercise or physical activity, but one will be working predominately harder or more consistently than the others. The key to which energy system is in the driving seat lies within the duration of the exercise being completed and the intensity of it. 

For example, a marathon runner will utilize more aerobic capacity due to the long duration of the event, whereas a 100 m sprinter will maximize their anaerobic, also called the phosphagen system, as a quick burst of high-intensity maximal force is needed. The glycolytic system is further broken down into fast and slow glycolysis. Fast glycolysis refers to pyruvate being converted to lactate which is faster but is limited in duration, while slow glycolysis allows a longer duration but is when pyruvate is shuttled into the mitochondria to undergo the Krebs Cycle (4). In football, certain movements such as jumping, sprinting, or turning direction maximally will require the anaerobic energy system to kick in, but athletes need to last a 90-minute period which draws on the aerobic energy system capabilities.  

“It is explosive actions such as sprinting, jumping, tackling and change of direction (COD) that seem to influence the outcome of games.” – Mujika et al., (2009).

Key Demands for Women’s Football

In a study by Krustrup and colleagues (2005), it was acknowledged that females spent 16% of their time standing, 44 % walking, 34 % on low-intensity activity and 4.8 % running at high intensity during a competitive match (5). Despite this study being completed over 15 years ago, some of the findings are still similar in the modern game concerning percentages around specific movements and time spent completing a given task. 

The key demands we must consider for women’s football are:

• Aerobic Capacity – VO₂ Max
• Strength & Power 
• Speed and Change of Direction
• High Intensity or High-Speed Running 

Aerobic Capacity 

Maximum oxygen uptake (VO₂ max) is defined as the greatest amount of oxygen that can be used at the cellular level for the entire body. It is often found to associate with an individual’s physical conditioning status and accepted use of measuring cardiovascular fitness (6). According to Iaia, Rampinini and Bangsbo (2009), aerobic energy production is highly taxed and accounts for more than 90% of total energy expenditure during a football match (7). 

Certain metrics such as age, gender, fitness levels and elevation can affect the final VO₂ max score reading. Pertaining to female football players, it has been reported that an elite player will report a VO₂ max score of 49.4 – 57.6 ml⋅kg⋅min^-1 (8). In perspective, the highest VO₂ max recorded to date is from cyclist, Oskar Svendsen, with a score of 97.5 ml⋅kg⋅min^-1 and long-distance runner, Joan Benoit, with a score of 78.6 ml⋅kg⋅min^-1. 

Table 1. shows a representation of VO₂ max scores for elite, highest division, and national team female soccer players. Similarly, to research conducted by Datson and colleagues (2014), all scores reflect the same metrics identified that an elite female soccer player needs to show to compete at the highest level. 

Speed and Change of Direction 

Speed is movement distance per unit of time and is often quantified as the time taken to cover a fixed distance (9). Figure 3 represents normative data reflecting different linear sprint times across various distances and levels for female soccer players. While Figure 4 pinpoints the number of sprint bouts that players racked up during a match. This normative data allows those specific teams to inform training demands to mimic the average sprints per game, or, if in pre-season to increase the load to entice a progressive adaptation. 

Table 2. Female soccer player’s sprint and agility performance as noted by Turner, Munro & Comfort (2020). 

Table 3. Female soccer player’s sprint performance as noted by Turner, Munro & Comfort (2020).

Agility is defined as the skills and abilities needed to explosively change movement velocities or modes (9). Often agility and change of direction coexists as one but agility explicitly refers to changing direction because of a stimulus and thus change of direction, simply being a pre-planned movement ahead of time. The terminology surrounding these words is important as a practitioner as in a competitive environment female soccer players will be continuously responding and reacting to a stimulus (players, ball etc.) which relates to agility-based movements. According to Bangso (1994), players perform a different action every 4-6 seconds throughout a match whereas Tuner, Munro & Comfort (2013) define it as 1,300 changes in each activity during a match setting, which equates to a change every 4 seconds. 

High-Intensity Running

High-intensity running, otherwise known as high-speed running, is the capability of athletes or players to perform short-duration sprints (< 10 seconds), interspersed with brief recoveries (< 60 seconds) (11). Elite-level athletes are typically able to clock up increased high-intensity runs per game, as well as distance, than non-elite athletes. Figure 5 represents normative data that can be used at the elite standard as a benchmark. 

Table 4. Turner, Munro & Comfort (2020) research findings show the number of high-intensity runs that occurred as well as the distance (km).

Strength and Power

Strength is the ability to exert force (N) to overcome resistance while power is defined as the ability to exert force in the shortest time (Power = Force (N) x Velocity (m/s)) (9). Strength and power movements are often imitated in football during tackles, jumping, heading, and diving. Referring to the energy systems, these movements are more anaerobic based due to the nature of explosive strength or power needed for a small duration of time. 

Table 5. A systematic review conducted by Datson et al. (2014) referencing various studies that completed the squat jump, countermovement jumps and drop jumps with their athletes. 

In normative data terms, often a 1RM test can be used to gauge strength levels, but often teams are looking at the Countermovement Jump as shown in the data presented in Figure 6. 

Considerations in Women’s Football

When working in women’s football some obvious, yet important, considerations that must be acknowledged are: 

1. Tactics 
2. Elite vs non-Elite 
3. Menstrual Cycle 
4. Injuries 

Tactics 

Every coach has a different philosophy and playing style which results in potentially different formations and tactics a player must understand. With different formations, a player’s role could change significantly, even if they are playing the same position. It is imperative that during the needs analysis, playing position is considered, as demands will naturally differ based on the role being played. 

It is frequently perceived that midfielders will complete the most running and therefore distance in a match with defenders likely covering more lateral distance and strikers less total distance but more sprint bouts. International and domestic normative data is available as shown in Figure 7, where the work of Andersson et al. (2010),  investigated the differences of players at club level and national level by playing position (12). 

Table 6. Defenders, midfielders, and forwards data at international level and domestic. 

A great tool to assist with player observation and the objective data collected is to ‘bucket’ players. The process of bucketing players allows tactics to be taken into consideration while focusing on detailed metrics the players can meet, relative to their position. Figure 8 shows an example of how two similar positions on the pitch, can have different outcome measures based on what metrics or capabilities could be looked at. Bucketing works in multiple ways outside of data analysis, it can work for injuries, personality traits, fitness testing scores and numerous other areas a multi-disciplinary team (MDT) may wish to focus on. 

Elite vs non-Elite

There is currently a huge gap in data between female athletes playing at an elite level, to those playing at non-elite. Non-elite teams often use their players as a normative data benchmark due to relevant research at the respective level just not being available or yet studied. Budgets, resources, training status and often quality is what separates the two. This is an important consideration to take into account as a coach or practitioner working at the non-elite level where players may have full-time commitments or work outside of training and game time. Being adaptable and keeping track of the player’s well-being must be at the forefront. 

Menstrual Cycle 

The menstrual cycle begins on the first day of menstruation which is when an athlete will be bleeding and persists until the start of the next period. A full cycle in academia is often referred to as 28 days, but this range can be anywhere between 21-35 days (13) and can vary from person to person. Each phase of the cycle should be treated as a separate hormonal profile, and the transition from one phase of the cycle to the next is complex, as the transition time is unclear, due to a lack of research within this area. 

Not all female athletes will have a menstrual cycle, some may be taking prescriptive contraceptive pills which is a further consideration to think about. During the various phases, different hormone receptors will be adjusted and show altered levels pending the stage in the menstrual cycle. Pre-ovulation will show high levels of estrogen but significantly low levels of progesterone but as the luteal phase occurs these levels almost flip flop, where progesterone is at its highest and estrogen tails off. 

Understanding the basis of the menstrual cycle will allow practitioners to work closely with their female athletes to best serve them, ultimately, keeping the athlete fit and healthy. The menstrual cycle must be treated as an individualized process as some athletes may suffer from heavy side effects, whereas some, may not report any during menstruation. A coach’s guide to the menstrual cycle assists with a more practical take away while a great resource to use is the Fitr Woman App, which provides detailed information and supports with tracking a menstrual cycle. 

Injuries 

A recent study in 2021 conducted by López-Valenciano and associates (15), showed a systemic review and meta-analysis of the injury profile within women’s football (see Figure 10). The results concluded that injury rates were higher in a competitive match setting, where per 1,000 hours of exposure, 19.2 injuries were likely to occur (15). Within this, 1.5 injuries were related to joint and ligament per 1,000 hours of exposure while 1.8 injuries to muscle and tendon-based injuries. Figure 11 reflects on the seasonal calendar year where injuries are more common, and clearly notes, there is a vast significant difference between late in the season compared to post, pre- and mid-season. As practitioners, the duty of care in the mid-late stages of a season must be accounted for. Utilizing health and well-being regular check ins, alongside subjective and objective measures will avoid injury rates spiking. 

The anterior cruciate ligament (ACL) repeatedly takes the headlines when women’s football is discussed in terms of injuries and the rising occurrence rate happening across the top leagues worldwide. ACL injuries are multifaceted, there are multiple reasons why they may occur; anatomy and biomechanics, pitch surface, shoe type, menstrual cycle and hormones, player load, historical injuries, quad-to-hamstring ratio and simply, a contact tackle, or non-contact movement. Drawing on previously conducted literature, some quick snap figures are reported below: 

72 % of ACL injuries occurred with non-contact mechanisms during sudden deceleration or landing manoeuvres (16). The rate of ACL injury occurrence in female athletes is higher in cutting, jumping, and pivoting sports compared with males (17). Female athletes were at nearly 4 times greater risk of injury than male athletes after having an ACL reconstruction surgery (18).

Data Analysis in Women’s Football

There are endless amounts of data points that can be collected and compared for an athlete or squad of players competing in competitive matches or training. The first step is to identify the global positioning system (GPS) in place and understand the terminology and data points being measured. Various companies will use different vocabulary, but often, relate to the same metric. Check out to data metrics measured below: 

• Catapult Sport
• STATS Sort
• Player Data

The ‘Rule of 3’

A top tip to allow data analysis to become more practical to best serve the athletes and build buy-in is focusing on 3 distinct areas and providing a rationale. A key example is noted below: 

High-Speed Running

Why? High speed running can assist in the improvement of a player’s aerobic endurance to maintain a high level of performance. This metric is often the huge gap between elite and non-elite in terms of distance and time spent on high-speed running or high-intensity running. 

Sprint Distance 

Why? Twofold. Firstly, inform training sessions to maintain match fitness based on athletes ‘average or normal’ sprint distance in a game. This avoids overtraining which could lead to injury and undertraining which can lead to fitness levels not being realistic to match the demands. Secondly, provide a structure for subs or players who do not play > 30 minutes, additional support is used with objective markers to make player specific and relevant. 

Accelerations and Deceleration Totals 

Why? The MDT has reviewed injuries from the past season which reported a high number of athletes suffering from hamstring injuries (whether small, medium, or long in duration and recovery). Tracking Accels and Decels can assist in determining overall hamstring health in relation to sprint and movement form. 

Before collecting any data it is crucial that you understand what GPS metrics you’d like to monitor and whether they are accurate or not. Data analysis requires buy-in from all MDT and players it touches and in this article, we explain how coaches and athletes can get the most out of GPS devices. 

Fitness Testing in Women’s Football

Fitness testing, also referred to as performance testing, is vital to create club-wide normative data that can be used as a benchmark to push athletes to improve and ultimately, enhance overall performance. Working in a MDT is fundamental to ask the following performance testing questions: which tests? Why these tests? When do we test and re-test? A consideration for ease of transparency and application is to create buy-in from the players. 

Possible aerobic capacity tests used to measure fitness levels for elite female footballers are:

• YoYo Intermittent Recovery Test 1
• YoYo Intermittent Recovery Test 2
• 1 Mile run
• 1.5 Mile run 
• Maximal Aerobic Speed (MAS)
• The Man United Fitness Test 
• The Cooper Run
• The Broncho Test 

Agility tests that are often used could be, not limited to, one or more of the following: 

• 5-0-5 Agility test
• Pro-Agility test
• T-Test
• Arrowhead test
• Illinois Agility test 
• Zig Zag test 

Sprint or speed tests often look to test an athlete’s maximal sprint across various distances such as 5 m, 10 m, 15 m, 20 m and even up to > 30 m. Keeping in line with the demands of the game, often most sprints that occur during a completive match do not exceed 10 m in distance (18), therefore, a practitioner may want to that this into account when selecting the correct linear distance to keep it specific as possible. 

Strength and power tests that are often used, not limited to, one or more of the following: 

• Countermovement Jump (CMJ) with and without arm use 
• 1RM test
• 3RM 
• 5RM 
• Squat Jump

Read more about the 4 Essential Tips for Administering Fitness Testing. For practitioners not working with gold-standard equipment or in non-elite environments, check out Fitness Testing on a Budget. 

Program Design Ideas for Women Footballers

Periodisation looks to segment an overall program into specific periods. The largest one, a macro-cycle, is often the entire year or a period of multiple months or years that frequently reflects all training and matches. Within the macro-cycle, a mesocycle resides, which could last several weeks or months. Finally, within the mesocycle, there may be one or more micro-cycles that could be a week long but could last up to four weeks (9). 

Working in women’s football, the best place to start is by looking at the overview of the entire season. Firstly, mapping out all known league matches, cup matches and any additional competitive fixtures that may occur. Around this, add in any contact time for technical and tactical sessions that the coaching staff wish to have. Once the macro-cycle is completed, the next step is to delve into a mesocycle block which may have coaching points, sessions or outcomes attached to them. 

The micro-cycles can be pre-planned in advance, but are often subject to change, based on previous results and match outcomes. Fixture congestion and fixture changes are quite possible, so being adaptable is the key. In the event a game goes into added time which was not previously accounted for, the MDT may look to utilize a longer active recovery session the following day, or possibly, give players the full day off. 

Speed, plyometrics and strength training can regularly be added into the main technical session as part of a warm-up or S&C segment. Specific sessions with a sole focus on speed mechanics may be beneficial, but for non-elite teams, it can be incorporated in creative ways during the regular training sessions scheduled. 

Conclusion 

The demands of women’s football that are outlined within this article aim to draw on all research conducted to date. With women’s football being banned for 50 years, the growth since 1971 has been on a constant rise, albeit, with the demands of the game changing to suit the times.   Completing a Needs Analysis is essential to understand the demands a player faces in a game and therefore, create training strategies to help bridge the gap. As different movements occur, football draws on both the aerobic and anaerobic energy systems. Often, a practitioner may look to investigate aerobic capacity, strength and power, agility and change of direction, and high-speed or high-intensity running. 

On the larger scale, normative data concludes that a female footballer should have a VO₂ max score between 49.4 – 57.6 ml⋅kg⋅min^-1. Other research states that changes of direction occur every 4-6 seconds during a game. Sprint distances look to vary based on position but are often recorded as > 10 m in distance. These demands allow training strategies to be implemented based on the findings that current research has to offer. Practitioners must take into account considerations of the tactics and playing style, the effects the menstrual cycle could impose, potential and common injury threats, and the gap between elite and non-elite levels. 

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