Muscle Cramping – More than Dehydration

Introduction

Gotta love academics! They define what we athletes know as a cramp this way: an exercise-induced muscle cramp is ‘a painful, spasmodic, involuntary contraction of skeletal muscle during or immediatley after exercise’. Research scientists have shown that the prevalance of cramping is as high as 37% in athletes. This review will highlight that the old theories of electrolyte imbalance as the cause of cramping are now being questioned. More importantly, we’ll use modern theories on cramping to highlight how to minimise their occurence during and after training or racing.

What are the Risk Factors?

Historically, numerous causes and thus risk factors have been implicated in cramping. These include:

  1. Accumulation of by-products of muscle metabolism that impair muscle contraction (e.g. lactic acid)
  2. Depletion of electrolytes such as sodium and potassium
  3. Loss of fluids and thus dehydration
  4. Extreme environmental conditions of heat and cold
  5. Lack of blood supply

However, while these are risk factors, previous and ongoing current research suggests they are not the causes of muscle cramps. Other factors have also been shown to increase the prevalence of cramping. These include:

  1. Having a history of cramping
  2. Competing at a faster pace than training pace
  3. Doing too much static (holding) stretching before racing
  4. Increased race duration and thus fatigue
  5. Not tapering enough before the race
  6. Racing with prior muscle fatigue or damage
  7. Muscles that cross two joints (e.g. hamstrings, quadriceps and gastrocnemius in the calf)
  8. Having a lower threshold frequency for cramping (15 Hz-cycles per second) than non-cramping people who have a threshold frequency of 25 Hz. This threshold frequency is the minimum frequency needed to stimulate a cramp. This thus suggests the nervous system is involved in some way.

What are the Theories?

The physiology of muscle contraction and relaxation may help explain the current theories. Three critical things need to occur for muscle contraction and relaxation. First, energy is needed for the muscle to contract and then relax. To do this, calcium in the muscles that stimulates the contraction must also be reabsorbed into pockets in the muscle so that the contaction stops. Dysfunction of either of these processes (calcium release and calcium reabsorption) can mean permanent contraction and thus contraction. Fatigue during exercise can cause this resorption of calcium to occur poorly. Thirdly, the electrical activity in the muscle must also be normal. If not, the muscle may be continually stimulated and thus contract and stay contracted. If any of the pathways that create this electrical activity are upset, the muscle may stay contracted. Again, fatigue can cause the muscle’s electrical activity to be upset.

In all the available literature, it appears that fatigue either within the muscle or within the nervous system itself may be related to cramping.

Treatment and Prevention?

Taken together, the above theories plus years of anecdotal evidence suggest the following ways to prevent cramping in athletes:

  • Carbohydrate and electrolyte supplements before ans during exercise may extend the time to fatigue and thus onset of cramping
  • Hydration before and during racing
  • Ensure you taper to reduce fatigue levels going into the race
  • Train at race pace leading into the event
  • Don’t overdo static stretching before the race, use dynamic stretching instead

If you get a cramp do passive stretching and consume fluids and electrolytes to alleviate the cramp the fastest.

Sources: 1. Buskard, A. (2014). Cramping in sports: Beyond dehydration. Strength and Conditioning Journal, 36(5): 44-52. 2. Minetto and others (2013). Origin and development of muscle cramps. Exercise and Sport Science Reviews, 41: 3-10. 3. Schwellnus, M. (2009).  Cause of exercise associated muscle cramps (EAMC)–altered neuromuscular control, dehydration or electrolyte depletion? British Journal of Sports Medicine, 43(6): 401-408.

Beta-Alanine: Might it be a Supplement of Choice for Masters Athletes?

Introduction

The use of dietary supplements in sports is widespread as athletes young and old are continuously searching for strategies to increase performance at the highest level. Beta-alanine is a supplement that is becoming increasingly popular over recent years. This review examines the available evidence regarding the use of beta-alanine supplementation and the link between beta-alanine and exercise performance in young and older people.

The Research

Beta-alanine supplementation is well-known to increase muscle carnosine levels. Carnosine is known to lower fatigue levelsand improve high-intensity exercise performance through buffering muscle acidity levels. It has been repeatedly demonstrated that chronic beta-alanine supplementation can increase intramuscular carnosine content. On the basis of its biochemical properties, several functions are ascribed to carnosine, of which intramuscular pH buffer and increasing the release of calcium in muscle to increase the force of muscle contraction are the most cited ones. In addition, carnosine has antioxidant properties, suggesting it could have a therapeutic potential in older athletes.

The suggested protocol for taking beta-alanine to increase muscle carnosine levels is taking up to approximately 4-6 gm per day over 4-10 weeks but in smaller regular doses in the day or using a slow-release tablet form. This is because taking more than 800 mg/day (approximately 10 mg/kg of body weight) has been shown to lead to parasthesia or a burning, tingling sensation in the skin. It appears that being an athlete in regular training increases the efficiency of the beta-alainine in increasing carnosine levels in muscles. Stopping ingestion  of the btea-alanine sees the carnosine levels return to pre-supplementing levels after 6-20 weeks. Maintenance of muscle carnosine levels appears to be maintained by beta-alanine intakes of about 1.2 gm/day.

What about the effect of beta-alanine supplementation on sports performance. Research suggest chronic beta-alanine supplementation increases muscle carnosine concentration leading to improved exercise performance in high-intensity exercise lasting 1-4 minutes after loading for 4 plus weeks. Some small but positive effect has been noticed in 2000m rowing performance (6-7 minutes all-out) but the effect drops off dramatically in longer endurance events. For example, in 2014, a study by Chung and others examined the effect of doubling muscle carnosine by supplementing with oral beta-alanine. Based on previous research that showed that muscle carnosine loading through chronic oral beta-alanine supplementation has been shown to be effective for improving short-duration, high-intensity exercise, the researchers wanted to see what effect it might have on one-hour cycling performance in athletes. 27 well-trained cyclists/triathletes were supplemented with either beta-alanine or a placebo (6.4 g/day) for 6 weeks. Time to completion and physiological variables for a 1-hr cycling time-trial were compared between pre-and post-supplementation. In conclusion, chronic beta-alanine supplementation in well-trained cyclists had a very pronounced effect on muscle carnosine concentration and a moderate buffering effect on the acidosis associated with lactate accumulation, yet without affecting 1-h cycling time-trial performance under laboratory conditions. Similarly, research has also shown that beta-alanine supplementation has no positive effect on repeat sprint performance such as that in road cycling or team sports.

In older non-athletes there is some evidence to suggest beta-alanine may have benefits on performance. Del Favero and others (2012) found that 3.2 gm/day of beta-alanine over 12 weeks improved time to exhaustion on the treadmill in 60-80 year old non-athletes compared to a control group. More recently, McCormack and others (2013) study examined the effects of an oral nutritional supplement fortified with two different doses of beta-alanine on body composition, muscle function and physical capacity in older adults. 60 men and women (age 70.7 ± 6.2 yrs) were randomly assigned to one of three treatment groups: 1) oral nutritional supplement (ONS; n = 20) (8 oz; 230 kcal; 12 g PRO; 31 g CHO; 6 g FAT), 2) ONS plus 800 mg beta-alanine (ONS800; n = 19), and 3) ONS plus 1200 mg beta-alanine (ONS1200; n = 21). Treatments were consumed twice per day for 12 weeks. At pre- and post-supplementation period, participants performed a submaximal cycle ergometry test to determine physical working capacity at fatigue threshold. Fat mass, total body and arm lean soft tissue mass were measured while muscle strength was assessed with handgrip dynamometry and 30-s sit-to-stand was used to measure lower body functionality. They showed that beta-alanine may improve physical working capacity, muscle quality and function in both older men and women. Previous research has also shown that carnosine levels in muscle decrease about 15-20% from youth to  middle-age with no decrease into older age. This might suggest that beta-alanine may have an even greater effect on performance than in younger people. However, no research to date has examined the effect of beta-alanine supplementation on performance in older male or female athletes.

Conclusions

On the basis of the high concentration of carnosine in human muscles, research supports it’s critical role in skeletal muscle physiology. Recent studies show that increasing carnosine levels through beta-alanine supplementation may improve muscle contraction forces and reduce muscle acidity levels in events lasting between 1-4 minutes.

While results from studies differ depending on the sample (e.g. young vs old; trained vs untrained), the most recent review of the research (Blancquaert and others, 2015), suggest the following:

  1. Chronic beta-alanine supplementation increases muscle carnosine concentration leading to improved exercise performance in high-intensity exercise lasting 1-4 minutes after loading for 4 plus weeks.
  2. Exercise training and co-ingestion of beta-alanine with meals can improve the efficiency of beta-alanine in increasing carnosine levels
  3. The exercise performance benefits of beta-alanine supplementing are equally effective in both trained and untrained individuals
  4. The increased muscle carnosine levels increase calcium release that excites muscle contraction. The increased carnosine also encourages a reduction in muscle acidity.

Sources: 1. Blancquaert, L and others (2015). Beta-alanine supplementation, muscle carnosine and exercise performance. Current Opinions in Clinical Nutrition and Metabolic Care, 18(1): 63-70. 2. Chung, W. and others (2014). Doubling of muscle carnosine concentration does not improve laboratory 1-hr cycling time-trial performance. International Journal of Sports Nutrition and Exercise Metabolism, 24(3): 315-324. 3. McCormack and others (2013). Oral nutritional supplement fortified with beta-alanine improves physical working capacity in older adults: a randomized, placebo-controlled study. Experimental Gerontology, 48(9): 933-939. 4. Del Favero and others (2012). Beta-alanine (Carnosyn™) supplementation in elderly subjects (60-80 years): effects on muscle carnosine content and physical capacity. Amino Acids, 43(1): 49-56.

Having a Nutrition Strategy Improves Endurance Performance

Introduction

It never ceases to amaze me how few athletes young or older (not old!) go into an endurance race without a nutrition plan. Here is some recent research evidence from Denmark highlighting that using a scientifically-based nutrition plan can improve race speed by close to 5%.

The Research

The researchers investigated whether a marathon run (42.2 km) was completed faster by applying a scientifically-based rather than a freely chosen nutritional strategy. Importantly from an applied perspective, gastrointestinal symptoms were also examined and reported. 14 non-elite runners performed a 10 km running time trial 7 weeks before the Copenhagen Marathon 2013 for estimation of running ability. Based on that time, runners were divided into two performance-matched groups that then completed the marathon by applying either of two race nutritional (gels and water) strategies – one they chose themselves, the other scientifically-based and given to the runners in that group under instruction from experts in the sports nutrition field. Runners applying the freely-chosen nutritional strategy (n = 14; 33.6 ± 9.6 years; 1.83 ± 0.09 m; 77.4 ± 10.6 kg; 45:40 ± 4:32 min for 10 km) freely choose their in-race food and water intake. Runners applying the scientifically-based nutritional strategy (n = 14; 41.9 ± 7.6 years; 1.79 ± 0.11 m; 74.6 ± 14.5 kg; 45:44 ± 4:37 min 10 k time) were targeting a combined in-race intake of energy gels and water, where the total intake amounted to approximately 0.750 L water, 60 g maltodextrin and glucose, 0.06 g sodium, and 0.09 g caffeine per hr. Gastrointestinal symptoms were assessed by a self-administered post-race questionnaire.

The runners in the scientifically-based nutrition and fluid group took in the following:

  • 2 energy gels (each gel contained 20 g maltodextrin and glucose, 0.02 gm of sodium and 0.03 gm caffeine) and 200 ml of water 10-15 minutes before the start of the marathon
  • 1 energy gel after 40 minutes of running and 1 gel every 20 minutes after that until finishing
  • water was encouraged at every one of the 10 water stations with 750 ml per hour the recommended target with each station having each individual athlete’s recommended water intake. Runners were encouraged to stop and drink

The Results

Marathon time was 3:49:26 ± 0:25:05 for the runners applying the freely chosen and and 3:38:31 ± 0:24:54 hr for the scientifically-based strategy nutrition and water intake strategy. The difference was statistically significant and represented a 4.7% faster marathon when using the scientifically-based nutrition plan. Some of the runners experienced diverse serious gastrointestinal symptoms (e.g. urge to defecate, reflux, bloating, vomiting, abdominal pain, diarrhoea, muscle cramps, urge to urinate, dizziness), but overall, symptoms were low and not statistically different between groups.

So What?

The sport scientists concluded that non-elite runners completed a marathon on average 10:55 min (4.7%) faster by applying a scientifically-based rather than a freely chosen nutritional strategy with both groups having the same incidence of gastrointestinal upsets. In endurance races I often see or hear of well-prepared athletes who train the house down but forget race nutrition. These same athletes say they were worried about getting gut upsets, the lack of gels etc being available on the race course or hard to find and buy, or that simply did not know what the scientific principles of race nutrition are. These present findings tell you to learn what these principles are and prepare yourself rather than relying on the race organisers. When it comes to race day nutrition I’ve always worked on the 6P’s Principle – Perfect Preparation Prevents Piss-Poor (pardon the french!) Performance or another well known saying, Failing to prepare is preparing to fail. For more detailed information on nutrition before, during and after training or racing, see Chapters 6, 15 and 16 of my book The Masters Athlete.

Sources: 1. Hansen, E. and others (2014). Improved marathon performance by in-race nutritional strategy intervention, International Journal of Sport Nutrition and Exercise Metabolism, 24(6): 645-655. 2. Pfeiffer, B. and others (2012). Nutritional intake and gastrointestinal problems during competitive endurance events. Medicine and Science in Sports and Exercise, 44(2): 344-351. 3. O’Neal, E. and others (2011). Half-marathon and full-marathon runners’ hydration practices and perceptions. Journal of Athletic Training, 46(6): 581-591.

Which Muscle Groups Need Work As We Age?

Introduction

We know by our own experience and looking at veteran track and field records at state, national and world level that masters athletes get slower with age. We also know muscle mass and strength and power of the lower limb muscles decreases, thus compromising both our strength and power that can be applied by the muscles to move us forward during sprinting.

During walking, we know that the plantar flexor (push-off muscles) reduce in power as we age and we rely more on the hip and knee extension muscles to walk at any speed.

As we move from walking to running, we need over twice the ground reaction force to be generated by the lower limb muscles. Research has shown that in veteran sprint runners, at any given speed, the vets have a lower ground reaction force and take shorter steps at a higher stride frequency than younger sprinters. Research has also shown that vets demonstrate greater knee flexion (bending) at initial ground contact, but lower knee bending during the first half of the stance phase. Vets also have increased ground contact time compared to younger sprinters.

Only a few studies have compared lower limb joint kinetics in young versus veteran runners. Both showed that the vets have lower power generation in the ankles but have similar power generation in the knees and hips. However, these two studies looked at running speeds of 2.7 m/sec (9.7 km/hr), not sprint running speeds.

Recently, some Finnish sport scientists, one a good buddy of mine, examined power outputs at the ankles, knees and hips during walking, running and sprinting in competitive male athletes (sprinters and long jumpers).

The Research

They compared three age-groups: young (26±6 years), middle-aged (61±5 years) and old (78±4 years) with 13 runners in each age group. Each athlete did three walking trials at a self-selected speed, three running trials at 4 m/sec (14.4 km/hr) and then two 60 m sprint efforts at their maximum speed. The researchers used an 8-camera video-recording system with markers attached to joints plus five force platforms to record joint angles and ground reaction forces.

The Results

The researchers found age-related decreases in ankle plantar flexor power generation became greater as speed changes from walking to running to sprinting. As a result, the older sprinters generated relatively more power at the knee and hip extensors than their younger counterparts when walking and running at the same speed. During maximal sprinting, young adults with faster top speeds demonstrate greater power outputs from the ankle and hip joints, but interestingly, not from the knee joint when compared with the middle-aged and old adults.

 So What?

Taken together, these findings show that decreases in ankle power contributes most to the age-related decline in running and sprinting speed. In addition, reduced muscular output from the hip rather than from knee limits the sprinting performance in older age.

This means that veteran power athletes need to put a greater emphasis on ankle and hip power development. This strongly suggests a combination of plyometric and power-focused resistance training in the gym is critical for the veteran track and field athlete and maybe sprinters in other sports. Specific exercises to develop ankle, knee and hip strength and power are shown in Table 1 below.

Table 1: Gym-based and plyometric exercises to develop ankle, knee and hip strength and power.

Joint

Gym-Based Exercises

Plyometrics

Ankle

Calf raises, Inverted leg press with plantar flexion, Squats with   plantar flexion.

Quick feet drills using ladders, two legged jumps > hops, two-legged   box-jumps > single legged box-jumps

Knee

Squats, Push press (front), Split squat, Inverted leg press, Lunges,   Power cleans

Cone hops, double-legged jumps, standing triple jumps, bounding, step   jumps, hurdle jumps, squat jumps

Hip

Squats, Push press (front), Split squat, Inverted leg press, Lunges,   Power cleans, Hip flexors

Cone hops, double-legged jumps, standing triple jumps, bounding, step   jumps, hurdle jumps, squat jumps, hill sprints, sled drives

 

I strongly recommend the advice and input of both a sports physiotherapist (to examine veteran athlete muscle weaknesses and imbalances) and a strength and conditioning expert to develop a specific gym-based and plyometric training program for each individual athlete.

Critically, ensure you make them aware that the older the veteran athlete, the greater the emphasis needs to be on ankle and hip strength and power development.

For more information on developing speed, strength and power, check out chapters 7 (Strength and power training for the masters athlete) and 8 (Speed and power training for the masters athlete). Two of 18 highly applied and evidence-based chapters from my book The Masters Athlete. The book and individual chapters are available as pdf’s too.

Source: Kulmala, J-P. and others (2014). Which muscles compromise human locomotor performance with age? Journal of the Royal Society Interface, 11: 20140858.

Do Compression Socks Work in Endurance Sport?

Introduction

Whenever I watch an Ironman on TV, read a Triathlon magazine, or check out results online from major triathlons, I see elite Ironman triathletes wearing compression socks. Theoretically, I can understand why they might work, especially in the heat. When on your feet for a long time, especially in hot conditions, fluid and blood tend to pool in the lower limbs. It’s the reason your foot fills out a shoe when running or walking for a long time. The compression stockings may help return this fluid to the heart. But what does the research say when it comes to the compression stockings improving performance or preventing muscle soreness in the days after the event? Here is some Spanish research suggesting they don’t work!

The Research

Expereinced triathletes aged around 35 years of age were matched for age, height, weight, and training status (swim 5-6 hr/week; ride approx 170 km/week; run approx 35 km/week; best half ironman time of approx. 5 hrs) and placed into either an experimental group (N = 19; using ankle-to-knee graduated compression stockings) or control group (N = 17; using regular socks). Participants competed in a half-ironman triathlon in environmental conditions of 29 ± 3 °C and 73 ± 8 % of relative humidity. Race time was measured by means of chip timing. Pre- and post-race, maximal jump height and leg muscle power were measured along with blood myoglobin and creatine kinase concentrations (markers of muscle damage) were determined and the triathletes were asked for perceived exertion and muscle soreness scores using standard measurement scales.

The Results

Total race time was not statistically different between groups (315 ± 45 min for the control group and 310 ± 32 min for the experimental group). After the race, jump height (−8.5 ± 3.0 versus −9.2 ± 5.3 %) and leg muscle power reductions (−13 ± 10 versus −15 ± 10 %) were similar between groups. After-race myoglobin and creatine kinase concentrations, the measures of muscle damage, were not different between groups. Perceived muscle soreness  and the rating of perceived effort were not different between groups after the race.

So What?

The results strongly suggest that wearing compression stockings did not represent any advantage for maintaining performance or reducing blood markers of muscle damage during a triathlon event. While some previous laboratory-based research suggests may enhance recovery of muscle strength and power and possibly lessen muscle soreness after exercise done in labs, this study in the real world suggest that compression socks don’t provide any advantage in improving performance or recovery in endurance athletes. For recovery strategies that research has shown work, see Chapter 15 of our book The Masters Athlete.

Source: Del Coso, J. and others (2014) Compression stockings do not improve muscular performance during a half-ironman triathlon race. European Journal of Applied Physiology, 114: 587–595.