Patent Application: US-201213633002-A

Abstract:
beverages comprising sodium ion in an amount correlated to the sodium ion concentration of a subject &# 39 ; s sweat used to prehydrate before exertion or to restore lost electrolyte and water resulting from physical exertion . such use can avoid or substantially reduce losses in performance and , in cramp prone individuals , avoid or substantially reduce cramping brought on by physical exertion .

Description:
in a preferred embodiment of the invention , an individual desiring to optimize his / her performance during competition or other exertion is tested under controlled conditions to determine the sweat sodium content of their sweat , usually in millimoles per litre ( mmol / l ), under controlled conditions . we have used the macroduct ™ and nanoduct ™ systems for testing sweat sodium concentrations in elite athletes . to date we have performed over 500 sweat tests on sporting disciplines ranging from motorsport , triathlon , endurance running and team sports such as soccer , rugby and cricket . all tests described herein were performed on physically active people and elite athletes competing at the highest level of the sport nationally and internationally including national squads . therefore the observations we have made apply as well to persons who engage in occupational or other activities that require substantial physical exertion and elite athletes . sweat rate is determined , for example , by measuring net weight loss over time during a period of exercise or exposure to elevated temperature , for example an hour of exercise or temperature exposure or a combination of both . net weight loss is determined by comparing the difference in weight before and after exertion and be adjusted for the weight of any food consumed during exercise and urine losses . based on these measurements , we have found that electrolyte concentration in and the volume of rehydration beverage required can readily be determined for individual subjects . however , we have also found that , based on the sodium content of sweat , persons can be conveniently classified into groups which permits determination of the sodium content of a limited number of formulations which will adequately serve the great majority of subjects without the need to resort to individualized prescriptions . we have found that generally satisfactory results can be obtained by classifying individuals in one of four groupings for this purpose . these groups can be denominated as follows : those skilled in the art will appreciate that additional levels of segregation of persons into groups based on the sodium content of their sweat may provide further assurances that an individual &# 39 ; s needs will be met . however , it is our experience that many persons engaged in physical exertion lack the opportunity to benefit from “ fine tuning ” their rehydration requirements because of the inability to suspend activity for the purpose of rehydrating frequently or at fixed intervals . seventy six females and 63 males were tested from our initial 139 athletes . the mean nacl equivalent for all 139 athletes was 46 . 0 ± 14 9 mmol / l ( range 21 - 81 mmol / l ). the values for the athletes are shown in fig1 . using the value of 0 . 89 to correct nacl to na as seen in the paper by riedi 3 , this gives a mean sweat sodium level of 41 . 1 ± 12 . 6 mmol / l ( range 19 - 72 mmol / l ). the scatter plot is shown in fig2 . from 342 tests undertaken in athletes and professional squads , an evaluation of sweat sodium levels was made between those that described as cramping ‘ often ’ or ‘ always ’ and those the ‘ never ’ cramped . 146 athletes had no history of cramping while 71 cramped ‘ often ’ or ‘ always ’. the mean sweat nacl reading on the macroduct system in the ‘ often ’ or ‘ always ’ crampers was 52 . 5 mmol / l and 42 . 5 mmol / l in the ‘ never ’ group . this was a statistically significant with a p - value of & lt ; 0 . 001 ( wilcoxon rank sum test ) and supports our earlier findings in the previous patent ( mean 56 . 2 ± 15 . 1 vs . 41 . 0 ± 11 . 6 ). an analysis was undertaken to assess if salt residue on the athlete &# 39 ; s skin is an indicator of high sweat sodium levels . athletes who reported a salt residue had a mean of 48 . 8 ± 16 . 0 while those that did not had a mean of 42 . 9 ± 12 . 9 . statistical testing did not show significance although the p - value approached significance at 0 . 07 ( 2 - tailed mann - whitney test ). athletes with salt craving did not have higher sweat sodium losses . those with cravings had a mean of 47 . 8 ± 15 . 6 while those without had means of 48 . 0 ± 14 . 2 ( p = 0 . 8 ; 2 - tailed mann - whitney test ). athletes describing a clear history of performance fade in the heat did not have a higher sweat sodium level compared to those with no performance fade . mean 46 . 8 ± 16 . 4 vs . 47 . 9 ± 14 . 4 (( p = 0 . 7 ; 2 - tailed mann - whitney test ). interestingly , males ( n = 63 ) had a significantly higher sweat sodium level compared to females ( n = 76 ). mean 51 . 7 ± 14 . 8 vs . 41 . 6 ± 12 . 0 ( p & lt ; 0 . 001 ; 2 - tailed mann - whitney test ). therefore , the data by sweat testing for elite athletes along with hydration formulations for optimal rehydration treatments indicates a system can be developed for individualized performance optimization . the precision hydration ( ph ) system utilizes the following process to tailor a hydration and sodium replenishment solution for an individual : 1 ) sweat analysis is conducted by obtaining a sweat sample from the individual and measuring the nacl content , preferably using the wescor - ellitech macroduct ™ or nanoduct ™ system although other tests providing similar results can be used in the practice of the invention . 2 ) the sodium equivalent is calculated from this nacl reading and extrapolated to give a net sodium loss per litre ( milligrams , millimoles or milliequivalents per liter of sweat . 3 ) the individual &# 39 ; s sweat sodium concentration is categorized into 1 of between 3 and 8 categories ( ranging very low to very high ). as indicated above , preferably at least four classifications of sweat sodium concentration are used . 4 ) the individual &# 39 ; s sweat rate is determined ( either by estimation or measurement of weight loss during a simulated exercise bout or heat exposure ). 5 ) various other factors including but not necessarily limited to the amount of exercise and / or heat exposure the individual undertakes , duration of exercise sessions or working shifts , pre - existing tendencies to suffering muscle cramps are recorded . 6 ) from the result of the sweat analysis / categorization , sweat rate data and other factors recorded in point 5 a hydration strategy built up from a suite of rehydration formulations is recommended . the preferred formulations contain various strengths of sodium from 250 to 1500 mg / litre . recommendations are made as to what the individual should drink for background hydration on a day to day basis , for rehydration during low / moderate exercise or heat stress situations and during levels of high exertion or high heat stress and for periods of recovery post exercise . more than one formulation will be recommended to suit the individuals &# 39 ; different circumstances and complete their regimen . 7 ) the hydration strategy can be manipulated by the individual at any time by utilizing an online portal along with a mathematical formula or manually on reviewing individual performance in the face of changing circumstances where any of the inputs can be modified in the face of changing circumstances and behaviors ( for instance competing in a longer race , increasing or decreasing volume of exercise undertaken , travelling to a much hotter / cooler climate ). the compositions of the present invention contain or are intended to be dissolved in water . as noted above , the concentration of electrolytes in a particular formulation are intended to substantially restore the amount of an electrolyte , particularly sodium , that is lost during exertion and to replace the volume of water lost as sweat and by other metabolic processes such as , for example , urination . preferably , the compositions comprise , as an aqueous solution , from at least about 200 mg of sodium per liter of water to about 2000 mg of sodium per liter of water . the compositions can be in the form of a powder or tablet but are formulated to be readily soluble in an amount of water that results in concentrations of sodium within the aforementioned range . as noted , the compositions may contain other cationic electrolytes , particularly potassium , magnesium ( as mg + 2 and calcium ( as ca + 2 ) in addition to sodium . preferably , the ranges of the amounts of these cations per liter of water are : potassium 100 to 700 mg calcium 20 to 250 mg magnesium 5 to 125 mg customised hydration recommendations based upon sweat sodium analysis values and the formulations listed above resulted in better performance and reduced cramping . to date we have tested over 500 athletes at the highest level in their sport and physically active persons . the sporting disciplines and level of competition and occupations include : professional football and rugby teams national senior and u19 women &# 39 ; s football squads national men &# 39 ; s and women &# 39 ; s rugby squad motorsport drivers including those at formula 1 and world rally championship level international level cricket players ironman level tri - athletes elite class cyclists elite level ultra - endurance athletes fire - fighters soldiers initially athletes / players / persons are classified solely by sweat sodium analysis as low ( l ), low / medium ( lm ), medium / high ( mh ) or high ( h ) using the mmol / l values described earlier . each classification has its own recommendation for drinks to use as background hydration , training hydration and race / competition hydration . if however any of the following conditions apply then an individual athlete ( or group of athletes ) will have their strategy up graded to the next strategy ( to account for increased sodium losses or counter symptoms of low sodium such as cramping ): 1 ) cramper ? if yes ( answers often or always to cramping question in questionnaire ) then automatically up - rate to next strategy , unless already in h . 2 ) training volume & gt ; 14 hr per week . if training volume exceeds 14 hours per week then automatically up - rate to the next strategy . 3 ) expected ambient conditions above 27 degrees c . if yes then automatically up - rate to next strategy ( works cumulatively with other factors if applicable — e . g . a cramper in 27 + degrees c . moves up 2 classifications as would over an athlete training & gt ; 14 hrs per week training in 27 + degrees c .) background hydration ( training ) h2prohydrate 250 or h2prohydrate 500 training hydration h2prohydrate 1500 race hydration h2prohydrate 1500 on non - training days background hydration recommendation is usually water or h2prohydrate 250 . the only exception being when an athlete is in a period of ‘ preloading ’ ( described below ). sodium preloading is recommended in certain conditions such as long duration ( more than 2 hours ) high intensity exercise with elevated ambient temperatures where anticipated losses are likely to be greater . in this scenario it is recommended to use the same formulation as their training hydration formulation for background hydration in the 48 hours prior to the activity . for example an athlete using the m / h strategy would replace h2prohydrate 250 or h2prohydrate 500 as their background hydration drink with h2prohydrate 1000 for 48 hours prior to competition only . athletes sweat rates vary considerably from person to person and for the same person in different ambient conditions and at different work rates . replacement of sweat losses can be governed by subjectively using thirst as an indicator , or objectively using weight loss , urine osmolality or specific gravity , urine colour ( urine armstrong chart ) amongst other established methods . furthermore , the volumes to be replaced vary from sport to sport . for example , in a short duration high intensity sport , the athlete may choose not to replace 100 % of losses . we make broad recommendations on volume replacement using established principles : 1 ) drink to thirst the prescribed h2pro fluids depending on whether they are background fluids , training fluids or race / competition fluids . 2 ) aim to maintain pale urine output ( grade 1 - 3 on armstrong urine chart ). 3 ) aim to replace between 70 and 100 % of fluid losses measured by bodyweight during a training session or race / game . what we are most concerned with doing is closely matching the composition of the fluids they are consuming to what is being lost in order to restore both sodium and fluid volumes efficiently . 1 ) sweat testing along with drink formulations results in better athletic performance . a ) small group study . three “ high salt sweaters ” (& gt ; 70 mmol / l ) were evaluated in a randomized cross - over study . the athletes were allowed 72 hours of pre - test hydration along with ad libitum fluid intake using either h2prohydrate 1500 versus a commercial drink ( elite water containing 125 mg / l of sodium ). the athletes were subjected to a 30 degree celsius heat chamber for 60 - 90 minutes and were then placed on a 90 minute run with pace fully controlled by the athlete . following the consumption of ad libitum h2prohydrate 1500 containing 1500 mg sodium per litre during the chamber exposure , there was a 5 %- 8 % increase in the distance run by the athletes , which corresponds to approximately 1 additional mile distance in 90 minutes . b ) individual performance gain — lab study . a ‘ high salt sweater ’ ex - ironman and international elite athlete was asked to drink a regular low sodium sports drink ( gatorade ) for 3 days while maintaining a regular diet and lifestyle . the athlete was then exposed to a performance treadmill test in a heat chamber at hot and humid simulated conditions and exercised to exhaustion . the test was repeated 2 weeks later but this time the athlete prescribed ad libitum formulation drink with sodium levels appropriate to his sweat test ( h2prohydrate 1500 containing 1500 mg sodium per litre ) which was consumed during the 2 week interval while maintaining the same diet and lifestyle as previous to the h2prohydrate 1500 consumption . the athlete achieved a greater distance under the same heat , humidity and exercise conditions as above which was linearly extrapolated to an extra 1 . 3 miles at 90 minutes . c ) team sport performance gain ( evidence provided by squad doctor ). a mid - 20 &# 39 ; s female playing for an international rugby squad previously fatigued at 40 - 60 minutes and had to be called off the field for performance fade . at this stage she would complain of cramp while also ‘ running out of steam ’. she was subjected to several medical tests with negative results . during squad sweat testing she was found to be a high salt sweater and prescribed a hydration strategy appropriate to her composition and volume losses . the strategy consisted of a high sodium drink equivalent to h2prohydrate 1000 ( 1000 mg sodium / l ). since then she has played full games and remains a key try scorer . her performance is more stable and predictable . 2 ) sweat testing along with drink formulations results in cramping cessation . a 36 year old businessman who is a keen endurance runner and has participated in the sport for several decades , during which he trains between 10 km to full marathons and trains 4 - 5 times per week ( averaging 50 miles ). in 2008 , at 19 miles during a marathon he had cramps in his thighs and calves . in 2009 in two races these symptoms recurred at 21 miles and 23 miles distance and affected his hamstrings and latterly his left arm . in 2010 , the cramps started at 18 miles and in this marathon he completed the distance but suffered headaches . his fluid regime during the races was water supplemented with salt tablets to approximately 200 mg sodium per hour . during his running assessment he lost 2 . 3 kg in weight translating to 2 . 3 l of sweat per hour making him a high volume sweater . sweat sodium values were measured and were 59 mmol / l making him a high salt sweater . the runner was put onto a regime which involved electrolyte consumptions using h2prohydrate 1500 above and this strategy resulted in the runner being able to compete and complete marathons and ultra - marathons without suffering cramps . his regime was as follows : 1 . pre - race ( 36 hours pre - race ) hydration with high electrolyte fluid containing 720 mg / l . and maintain pale urine ( armstrong grade 1 , 2 or 3 ). 2 . race hydration with 1000 mg / hr sodium and aim to consume at least 75 % of weight lost per hour . for example , if 1 . 0 kg is lost per hour then replace with at least 750 ml of water . from 342 tests undertaken in athletes and professional squads , an evaluation of sweat sodium levels was made between those that described as cramping ‘ often ’ or ‘ always ’ and those the ‘ never ’ cramped . 146 athletes had no history of cramping while 71 cramped ‘ often ’ or ‘ always ’. the mean sweat nacl reading on the macroduct system in the ‘ often ’ or ‘ always ’ crampers was 52 . 5 mmol / l and 42 . 5 mmol / l in the ‘ never ’ group . this was a statistically significant with a p - value of & lt ; 0 . 001 ( wilcoxon rank sum test ) and supports our earlier findings in the previous patent ( mean 56 . 2 ± 15 . 1 vs . 41 . 0 ± 11 . 6 ). having looked at cramp - prone and non - crampers , we have found that the cramp - prone athletes have significantly higher sweat sodium levels compared to non - crampers . also , net sodium losses taking into account their sweat volume loss are higher . following the sweat analysis , the athletes were given drink formulations appropriate for their respective sweat sodium levels . to date , all “ cramping ” athletes ( a 100 % response ) given the prescription of sports drink formulation with the appropriate levels of sodium to the cramp - prone population have reported a complete cessation or dramatic reduction in their cramping symptoms . the hydration regime given to the players was to replace between 75 % to 100 % of their sodium losses depending on the duration and intensity of the sport / race . those that have failed to continue their prescribed drinks have experienced rebound cramping . 3 ) randomized multi - athlete trial comparing hydration with h2prohydrate six male elite athletes were randomized into two cohorts in order to test the effect of electrolyte replenishment in accordance with the present invention on physical and cognitive performance during and after controlled physical exertion . the members of one of the cohorts were randomized to a hydration regimen in which they hydrated using evian bottled water while the members of the other cohort hydrated using one of the h2prohydrate formulations described above . the particular h2pro formulation used by an athlete was selected based on his sweat classification determined as described above . the hydration regimen was initiated 72 hours before controlled physical exertion was initiated and maintained during the exertion period . the athletes consumed their hydration beverage ad libitum . just prior to beginning the controlled physical exertion the athletes were subjected to the following tests : ( i ) urine specific gravity ; ( ii ) weight ; ( iii ) serum biochemistry to determine lactate , sodium and creatinine levels ; ( iv ) batak wall scoring ; ( v ) determination of wayne saccatic fixator score ; and ( vi ) stroop tests 1 & amp ; 2 . the results of these tests were used as a baseline for the measurement of the effects on the athlete of the controlled physical exertion . following performance of the baseline tests , each athlete was placed in a heat chamber where , using a stationary bicycle , he exercised at 70 % vo 2 max at 28 ° c . for one hour during and after which the foregoing identified tests were repeated . after 10 minutes , the athlete returned to the chamber and , using the stationary bicycle , performed a blinded ( to power output ) performance time trial of 15 minutes at maximum effort , following which the aforementioned tests were repeated again . two weeks after the initial chamber testing , the two cohorts switched hydration regimens and , again following a 72 hour period , the same baseline testing followed by controlled exertion and post exertion testing was repeated . the sodium sweat category of the six athletes and h2pro hydration beverage used by the athletes were as follows : the following results were observed for the six athletes based on the results of the tests : after 1 hour at 70 % vo 2 max at 28 ° c . : ( a ) an average of 4 . 4 % increase in power output ( watts ) was observed by athletes when hydrating with an h2pro formulation than when hydrating with water . high salt sweaters observed an even greater 8 . 8 % power increase when using an h2prohydrate 1500 formulation . ( b ) perceived exertion was lower ( borg scale ) for athletes on h2prohydrate formulations ( 16 . 03 ) compared to perceived exertion on water ( 16 . 27 ). again the results for high salt sweaters was even better on h2prohydrate 1500 ( 15 . 5 ) than on water ( 16 . 4 ). accordingly , hydrating with h2prohydrate permits the athletes to improve sustained power output without greater physical discomfort . ( c ) measured mean heart rate for athletes on h2prohydrate was 162 / min , a 4 . 3 % reduction over mean heart rate of 169 / min on water ; the measured mean heart rate for high salt sweaters on h2prohydrate 1500 was 168 / min compared to 158 / min on water , a 6 . 3 % reduction . thus hydration with h2prohydrate permitted greater sustained power output with less physiological stress . ( d ) the mean core body temperature of the athletes on h2prohydrate was 38 . 4 ° c . compared to 38 . 6 ° c ., demonstrating that sustained power output using customized hydration provided by h2prohydrate formulations results in less physiological stress . ( e ) mean lactate levels were very nearly the same ( 4 . 8 mmol / l ) when the athletes were on h2prohydrate formulations compared to measured levels when on water ( 4 . 7 mmol / l ) when hydrating with water , demonstrating that higher power output can be obtained on h2prohydrate with the same physiological stress seen when water is used for hydrating . ( f ) serum sodium levels for athletes on h2prohydrate remained above a baseline of 141 mg / l whereas serum sodium levels for athletes on water were at baseline and after exercise under 139 mg / l . this demonstrates that use of h2prohydrate formulations to hydrate reduces the risk of hyponatraemia . ( g ) serum creatinine levels ( baseline 100 ) for athletes using h2prohydrate formulations remained below 120 whereas for athletes on water the levels rose to a mean of 130 . this demonstrates that sustained exercise on h2prohydrate formulations results in less muscle breakdown than occurs with athletes on water alone . ( h ) the median specific gravity of athletes urine ( baseline 1 . 005 ) was lower after exercise for athletes on h2prohydrate ( 1 . 010 ) than for athletes on water ( 1 . 013 ) indicating better hydration ofn h2prohydrate . ( a ) an average of 7 . 3 % increase in power output ( watts ) was observed by athletes when hydrating with an h2prohydrate formulation than when hydrating with water . high salt sweaters observed a significantly greater 19 . 8 % power increase when using an h2prohydrate 1500 formulation . ( b ) mean batak performance for athletes on h2prohydrate increased from the baseline for athletes on h2pro formulations by about 5 . 3 % whereas batak performance of athletes on water decreased by 2 . 9 % from the baseline for those athletes . the largest increase in batak performance ( about 7 . 3 %) was seen for high salt sweaters . these results indicate that athletes on customized electrolyte replacement formulations increase their reaction times , particularly high salt sweaters . ( c ) the athletes also were tested using stroop 1 and 2 test regimens . essentially no difference in performance was seen overall for athletes on water compared to athletes on h2pro formulations . however , high salt sweaters showed an increase of about 9 . 5 % in reaction time when on an h2prohydrate formulation . ( d ) a test for hand / eye coordination was also performed on the cohorts of athletes . hydration with both water and customized electrolyte formulations resulted in some improvement for both dominant and non - dominant hand / eye coordination . the principal beneficial effect for users of h2pro formulations e was seen in high salt sweaters and especially for non - dominant hand / eye coordination . 1 . van der merwe d e , ubbink j b , de1port r , becker p , dhatt g s , vermaak w j . biological variation in sweat sodium chloride conductivity . ann clin biochem . 2002 ; 39 : 39 - 43 2 . m . heeley , d . woolf , a . heeley . indirect measurements of sweat electrolyte concentration in the laboratory diagnosis of cystic fibrosis . arch dis child . 2000 ; 82 : 420 - 424 3 . riedi c a , zavadniak a f , silva d c , franco a , filho n a . comparison of conductivity with sodium determination in the same sweat sample . j pediatr ( rio j ). 2000 ; 76 : 443 - 6 4 . bates p b , miller v s . sweat rate and sodium loss during work in the heat . j occup med toxicol . 2008 ; 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