Calcium and exercise performance -
Since calcium is a mineral, it is obtained only from the diet through absorption. However, the intestinal absorption of calcium is not very efficient and is influenced by many factors. It is stimulated by vitamin D 3 , sugars, some amino acids and certain short-chain fatty acids 7 , 8 , 9.
Because calcium and vitamin D are vital for bone development, calcium and vitamin D deficiencies in children and adolescents age 2—18 years; a period of fast growth lead to lower peak bone mass and higher risk of bone fracture later in life 10 and review article The leading causes of vitamin D deficiency in children and adolescents are less time spent outdoors, overuse of sunscreen protections and inadequate intake of food rich in vitamin D, particularly fish and functional foods nutrients that provide health benefits beyond basic nutrition which can reduce the risk of noncommunicable diseases It was reported that higher intake of calcium was associated with significant gains in hip bone mineral density BMD in young female runners 13 , increases in bone mineral status in adolescent girls 14 , and bone mineral density in Gambian children who had been on low calcium diet Our previous investigation showed that calcium in hydroxyapatite form had greater bioavailability than calcium carbonate.
Moreover, calcium supplementation from tuna bone was able to prevent lactation-induced bone loss in experimental animals Thus, fish bone is considered a good natural source of calcium supplementation. Besides, vitamin D 3 is essential for the musculoskeletal development and bone formation.
Since crude tuna head oil contains a high amount of vitamin D 3 and Omega-3 polyunsaturated fatty acids 18 , the latter of which, have been known to improve cognitive function and increase neuroplasticity, tuna fish oil could be one of the most effective and readily available sources of vitamin D supplement.
In addition, Omega-3, essential fatty acids, especially those from marine oils, could stimulate intestinal calcium absorption in vitro study as well as promote bone growth in young growing age 19 , Since females have greater risk of fragility fracture and osteoporosis than males, especially after menopause and becoming aging 5 , and since early bone health and peak bone mass in young adult potentially determine osteoporosis risk of females later in life 6 , we sought to develop calcium supplement products for females.
In the present study, we therefore performed all experiments only in female animals. It is well recognized that regular exercise provides several physiological and psychological benefits.
Previous experiment showed that weight-bearing exercise, such as forced treadmill running, in ovariectomized rats helped prevent reduction in trabecular bone volume and bone mineral density 21 , and even increased bone volume and thickness, osteoblast activity, and improved dynamic bone formation The conceptual idea of this study is to provide a new form of calcium supplement from a natural source for use during childhood and adolescence, i.
Combining exercise with calcium supplementation may provide additive effect on loaded bone, particularly tibiae and femora. In this section, there were 2 calcium diet formulae, i.
Calcium-replete diet was prepared by adding CaCO3 into L to obtain a final of 0. Rats fed either L or S1 exhibited an increase in bone growth as they got older from the age of 6 to 15 weeks. Th as analyzed by bone histomorphometry, increase in mechanical property as analyzed by 3-point bending, and increases in cortical bone mineral density BMD , cortical bone mineral content BMC , cortical thickness Ct.
Th , cortical area Ct. A of metaphyseal and diaphyseal mid-shaft femur as analyzed by pQCT. However, trabecular BMD and BMC did not change with increase in age in S1 reflecting the concurrent increase in the size of bone.
On the other hand, comparing adolescent rats fed low calcium diet for 2 weeks 6 week old L and young adult rats fed low calcium for 11 weeks 15 week old L , the week old L showed normal bone length and increased in bone weight, trabecular BMC, cortical BMC, Ct. Th and Ct.
Compared with corresponding S1 control, bones of rats after 2 and 11 week calcium insufficiency exhibited drastic reductions in bone mechanical properties, cortical BMD, cortical BMC, Ct.
Th, and Ct. A of metaphyseal and diaphyseal mid-shaft femur. Bone impairment found in rats fed low calcium for 11 weeks was less severe than those fed low calcium for 2 weeks.
However, trabecular BMD was significantly decreased after 11 weeks but not after 2 weeks of low calcium diet. Magnitude of changes in bone microstructural parameters in L compared with corresponding S1 after 11 weeks of low calcium diet were greater than those after 2 weeks of low calcium diet.
Blood chemical analysis revealed that dietary calcium insufficiency for 2 and 11 weeks led to hypocalcemia lower levels of total calcium and ionized calcium , lower level of 25 OH D 3 , and higher levels of inorganic phosphate only in 11 weeks and hormone 1,25 OH 2 D 3 Table 1.
All rats were challenged with low calcium diet L for 2 weeks, thereafter, the effect of calcium supplementation from tuna bone denoted as S2 was compared with calcium carbonate denoted as S1 Fig.
Fractional calcium absorption in young rats fed extra calcium from tuna bone was significantly higher than that of rats fed CaCO 3 Rats fed tuna bone calcium and CaCO 3 had similar body weight that increased with age from 6 to 10 weeks. Supplemental Table 4 showed no difference in tibial length or bone mechanical properties.
pQCT analysis of the femoral metaphysis and mid-shaft diaphysis showed no difference in BMD or BMC of trabecular Tb. BMD and Tb.
BMC , cortical and sub-cortical region Sub. BMD and Sub. BMC or cortical compartment Ct. BMD and Ct. Th, Ct. A, periosteal perimeter and endosteal perimeter Ps.
Pm and Es. Pm, respectively were not different Supplemental Table 4. Bone histomorphometry showed no difference in the microstructure, and osteoblast and osteoclast surface normalized with bone surface Fig.
However, rat fed calcium supplementation from tuna bone exhibited higher mineral apposition rate 2. Blood chemical analysis showed no difference in the levels of 25 OH D 3 , 1,25 OH 2 D 3 , and total calcium between these 2 treatments, whereas serum inorganic phosphate was lower in rats given tuna bone calcium supplementation Supplemental Table 4.
Tuna bone calcium supplementation resulted in higher fractional calcium absorption and bone formation rate than calcium carbonate supplementation. A Experimental design, all rats were challenged with low calcium diet 0. Extra calcium 0. Th, trabecular separation, Tb. Sp, trabecular number, Tb.
N, osteoclast surface normalized with bone surface, Oc. S1 , calcium supplementation in diet from CaCO 3 , S2 , calcium supplementation in diet from tuna bone.
The timeline for age-matched rats fed with calcium-replete diet from CaCO 3 S1 is shown in Fig. Timeline for rats on low calcium diet L and rats receiving 3 formulae of tuna calcium supplements after 2 weeks of low dietary calcium diet is shown in Fig.
The diet ingredients were shown in Supplemental Tables 1 and 2. To find the optimal treatment duration, we performed a preliminary study in 4-week-old young growing female rats by investigating the alteration of femoral trabecular bone mineral density BMD by using an in vivo micro-computed tomography Skyscan It showed that tuna bone calcium supplementation in 3 formulae for 4 and 9 weeks was able to completely restored bone loss to age-matched calcium-replete diet S1.
Therefore, we chose 9 weeks calcium supplementation for this study Supplemental Fig. Calcium supplementation from tuna bone, tuna bone with tuna head oil and tuna bone with 25 OH D 3 enhanced fractional calcium absorption.
A Experimental design, 4-week female rats were received calcium-replete diet 0. Thee-day calcium balance study was conducted in 3 time points, i. The differences between five experimental groups were determined by one-way ANOVA followed by Tukey post hoc test.
The three tuna bone calcium supplement formulae were tuna bone calcium S2 , tuna bone with tuna head oil added 25 OH D 3 S3 and tuna bone with commercial 25 OH D 3 S4. Tuna bone calcium supplement S2 diet was prepared by mixing 0. It showed that rats in groups S2 , S3 and S4 had similar body weight to those of L and S1 Fig.
The 6-week-old rats fed low calcium for 2 weeks during adolescence 4—6 week old were found to upregulate the fractional calcium absorption that remained significantly higher than in the age-matched S1 group when calcium insufficiency continued for another 4 or 9 weeks The week-old rats that received 4 weeks of calcium supplementation of S2 , S3 and S4 showed even higher fractional calcium absorption than those of L Fig.
However, fractional calcium absorption returned to the basal level after 9 weeks of calcium supplementation, i. Immunostaining of PMCA1, a calcium transporter expressed at basolateral membrane of enterocytes, which is responsible for pumping calcium out of the cell, showed increase in the protein expression in L compared with S1 , and the expression was compromised by calcium supplementation with or without 25 OH D 3 Fig.
As expected, urinary calcium excretion was significantly decreased in L Fig. While 4 weeks of calcium supplementation did not change urinary calcium excretion in L Fig. Serum level of 25 OH D 3 was consistently lower in L compared with the age-matched S1 Table 2. Similarly, the week-old B group show a significantly lower level of 25 OH D 3 when compared with S1.
However, 25 OH D 3 level of the week-old S2 was not different from that of S1. Supplementation of tuna head oil added 25 OH D 3 in S3 significantly increased the serum level of 25 OH D 3 in both and week old rats when compared with the corresponding L groups. Animals fed low calcium diet with or without calcium supplementation had higher serum level of 1,25 OH 2 D 3 at both 10 and 15 weeks of age compared with age-matched S1.
Low calcium diet also resulted in hypocalcemia and hyperphosphatemia. Calcium supplementation from S2 , S3 and S4 restored the level of ionized calcium and inorganic phosphate to the level seen in S1 , but the total calcium levels of S2 and S4 were still lower than that of S1 Table 2.
Femoral length of L group was not different from calcium-replete diet S1 , suggesting that calcium insufficiency in this study did not impair bone linear growth.
Rats fed tuna bone calcium supplement from 3 formulae also had similar bone length to L and S1 Table 2. Bones from L had lower dry and ash weight indicating lower mineral content.
Bone weight after calcium supplementation was fully restored to that of S1 Table 2. Representative coronal images of the micro-computed tomography scanning of femur at the age of 10 weeks and 15 weeks, i.
At the age of 10 weeks, L exhibited a drastically reduced metaphyseal trabecular bone area and mid-shaft cortical shell, whereas calcium supplementation in S2 , S3 and S4 groups resulted in greater trabecular bone area and thickening of the mid-shaft cortical shell.
At the age of 15 weeks, bones of every group were longer than those of the week-old animals and the effects of calcium supplementation were similar to those seen in the 10 week old animals Supp Fig.
Representative scanning images of the cross-sectional section of metaphyseal distal femur were shown in Fig. BMD and BMC of total tissue TOT; including trabecular and cortical compartments , trabecular and cortical compartments in L were drastically reduced when compared with S1.
As seen in Fig. A and Ct. Th were also lower than those of S1. The thinning of Ct. A in L apparently resulted from reduction in Ct. Pm without any change in Ct. All 3 tuna bone calcium supplement formulae i. BMD, TOT. BMC, Tb.
BMD, Tb. BMC, Ct. A, and Ct. Th with an exception of Ct. Pm and Ct. However, Tb. BMC of S2 , S3 and S4 were still significantly lower than S1 , while Ct.
BMD of S3 and S4 was significantly higher than that of S1 Fig. Figure 3 C depicted scanning images of the cross-sectional sections of femoral midshaft diaphysis. As expected, L had lower Ct. BMD, Ct.
A, Ct. Pm, and calcium supplementation from S2 , S3 and S4 restored these parameters to those of S1 Fig. Even though the cortical shell of both femoral metaphysis and diaphysis was thicker after calcium supplementation, bone growth in width was compromised as Ct.
Pm were significantly lower than those of S1 Fig. N and Tb. Th, and increase in Tb. Tuna bone calcium supplementation from S2 , S3 and S4 completely restored all values to the levels of S1 Fig. All three formulae of calcium supplementation were able to lower the maximum displacement from the level seen in L , but only the reduction in S4 was significantly different from that of L.
Changes in strain showed a similar trend to that of maximum displacement Fig. Calcium supplementation from tuna bone, tuna bone with tuna head oil added 25 OH D 3 and tuna bone with 25 OH D 3 mitigated calcium insufficiency-induced osteoporosis.
Four-week female rats were received calcium-replete diet 0. A Representative images of three-dimensional reconstruction of metaphyseal distal femur cross-sectional view , Scale bars, 1 mm, B bone mineral density and content BMD and BMC, respectively of total bone TOT , trabecular Tb and cortical compartment Ct.
Cortical area Ct. A thickness Ct. Th , periosteal perimeter Ct. Pm and endosteal perimeter Ct. Pm , all parameters were analyzed by pQCT at distal metaphyseal femur, C representative images of three-dimensional reconstruction of mid-shaft diaphyseal femur cross-sectional view , Scale bars, 1 mm, and D cortical bone parameters analyzed by pQCT at mid-shaft femur.
Calcium supplementation from tuna bone, tuna bone with tuna head oil added 25 OH D 3 and tuna bone with 25 OH D 3 improved bone microstructure impairments and mechanical properties. Experimental design was similar to Fig.
The experimental design to evaluate the effect of impact exercise and calcium supplementation on calcium and bone metabolism was shown in Fig. Animals that performed voluntary running exercise with calcium supplementation from tuna bone EB showed the same body weight gain as those of the exercise without supplementation group EL , and the sedentary with and without calcium supplementation groups SB and SL , respectively Fig.
EL and EB also demonstrated similar exercise performance as shown by cumulative running distance Fig. Similar to the experimental design in the first part, in this experiment, week and week old groups received calcium supplementation for 6 weeks and 12 weeks, respectively Fig. Tuna bone supplemented B groups exhibited lower fractional calcium absorption compared to age-matched control groups whether they were sedentary or voluntary exercise group In the 12 week old group, exercise had no effect on fractional calcium absorption in calcium insufficient L group, whereas in B group that were fed adequate calcium diet, exercise significantly decreased calcium absorption As for the 18 week old groups, exercise had no effect on fractional calcium absorption whether with or without calcium supplementation Fig.
Calcium supplementation had a tendency to increase urinary calcium excretion in sedentary group, but the increase reached a statistical significance only in the exercise group 5. Calcium supplementation suppressed fractional calcium absorption and increased urinary calcium excretion in both sedentary and exercise groups.
A Experimental design, 4-week female rats were challenged with low calcium diet for 2 weeks, thereafter, rats were randomly divided into 2 sets, calcium repletion diet 0. Each set, rats were randomly sub-divided into 2 groups, voluntary running exercise rats were housed in cage-equipped with running wheel for 12 weeks or sedentary rats were housed in cage-equipped with running wheel but wheel was locked for 12 weeks , B body weight, C cumulative running distance, D relative fractional calcium absorption at rats on age of 12 weeks and 18 weeks, and E 3-day urinary calcium excretion.
SL , sedentary with low calcium diet, SB , sedentary with calcium supplementation, EL , exercise with low calcium diet, EB , exercise with calcium supplementation. Representative 3D images of CT scanning of distal femur longitudinal section was shown in Fig.
Neither calcium supplementation from tuna bone nor running exercise had effect on bone length Table 3. On the other hand, it was clearly shown that calcium supplementation with or without exercise increased bone weight and improved bone microstructure by alleviating all calcium insufficiency-associated osteoporotic features.
Interestingly, running exercise without calcium supplementation L significantly increased Tb. Th of the diaphyseal mid-shaft femur. Neither calcium supplement nor exercise had effect on Ct. BMD of metaphyseal region.
The overall data from pQCT strongly suggested that calcium supplementation had greater benefits to bone than exercise.
Result from two-way ANOVA indicates that calcium supplement had effect on both metaphyseal and diaphyseal midshaft, while exercise had effect on bone predominately at the diaphyseal midshaft.
Moreover, the effect of calcium supplementation and exercise had interaction on Ct. BMD of diaphyseal midshaft. Data on blood chemical analysis showed that calcium supplementation in sedentary group, but not in the exercise group, significantly increased serum levels of total calcium and inorganic phosphate Table 3.
From the ultra-high resolution µCT analysis Fig. Sp in both sedentary and exercise groups. SB exhibited a higher Tb.
Th than SL. Calcium supplementation resulted in a lower trabecular connectivity density Conn. D in sedentary 8. Calcium supplementation with exercise increased Conn.
D more than calcium supplement without exercise Neither calcium supplementation nor exercise had effect on the degree of anisotropy. From the mechanical property analysis, exercise was found to significantly increase these mechanical parameters only in calcium deficient L groups, but not in calcium supplemented B groups.
In contrast, tuna bone calcium supplementation, whether with or without exercise, significantly increased the maximum load and stiffness, and increased yield load in the sedentary group Fig. Voluntary running exercise improved bone microstructure and mechanical property in calcium insufficiency-induced osteoporosis.
A Representative images of three-dimensional reconstruction of metaphyseal distal femur longitudinal view , B representative images of three-dimensional reconstruction of metaphyseal distal femur upper panels and diaphyseal mid-shaft femur lower panels , Scale bars, 1 mm, C bone microstructure analyzed by ultra-high resolution micro-computed tomography at distal femur, D mechanical properties analyzed by 3-point bending apparatus at femoral mid-shaft.
Low dietary calcium intakes and poor 25 OH D 3 status are common findings in children living in developing countries.
Low dietary calcium intakes are typically observed as a consequence of a diet deficient in dairy products and high in phytates and oxalates which reduce calcium bioavailability. Childhood and adolescence are the critical period of bone development and mineralization, and are the period for maximizing genetically predetermined peak bone mass.
Peak bone mass and subsequent bone losses are important determinants of osteoporosis later in life. Thus, maximizing peak bone mass in early life, a period of relatively high plasticity of the skeleton in response to physical forces, is advocated as a way to protect against osteoporotic fractures later in life.
It was shown that daily calcium intake was associated with mineral acquisition in adolescents in a dose response manner Thus, inadequate calcium intake during this critical period could reduce bone accrual and impede bone growth, which, in turn, reduced bone size.
This study aimed to investigate whether calcium supplementation as well as impact exercise was able to ameliorate bone defects caused by inadequate calcium intake in young growing rats.
According to the previous literatures, 4—6 weeks old in rats is considered young adult, which is a proxy of adolescence in human 30 , Creedon and Cashman 32 showed in young growing female rats fed low calcium diet between aged of 5—8 weeks that 5-week-old rats fed 0.
Therefore, 4-week old young growing female rats was used in this study and was challenged with 0. Herein, we demonstrated that the body could undergo significant adaptation to low calcium intake by reducing renal calcium excretion and increasing fractional intestinal calcium absorption through enhanced 1,25 OH 2 D 3 production.
Generally, bone mass and strength increased with age As expected, the week-old rats in the present study had higher bone mass at both cortical and trabecular regions compared to the 6-week old rats Table 1.
At the site of trabecular metaphysis, higher bone mass was detected by bone histomorphometry but not pQCT technique, which was probably due to the lower sensitivity of the pQCT technique. Two weeks of dietary calcium insufficiency led to a drastic reduction in trabecular BMC, cortical BMD and cortical BMC in both adolescent and young adult rats.
The reduction in trabecular BMC with no change in trabecular BMD in the adolescent 6-week-old rats was probably due to a parallel decrease in bone size and trabecular bone as shown by lower dry weight and ash weight Table 1.
The week old young adult rats that remained on low calcium diet for another 11 weeks showed clear impairment of bone growth as seen in all bone-related parameters except for bone length. Considering the impact of 2 and 11 weeks of low calcium diet on 6- and week old rats, respectively, on trabecular bone, reduction in trabecular bone volume in 6-week old low calcium rats was due mostly to decrease in trabecular thickness.
On the other hand, the drastic reduction in bone volume in week old low calcium rats was due to a decrease in trabecular thickness as well as a huge reduction in trabecular number. This study confirmed previous reports that inadequate calcium intake did not impair bone growth in length in young growing female rodents 34 , young adult male rodents 35 , and prepuberty girls However, it did impair the microscopic structure of bone that clearly compromise the mechanical properties and function.
Calcium supplements derived from natural sources are generally considered more beneficial than purified calcium carbonate from inorganic sources 37 , 38 , 39 , There are two important advantages for tuna bone as a calcium source.
First, calcium in tuna bone is a form of hydroxyapatite providing both calcium and phosphorus in an appropriate or optimal ratio , the nanocrystal of which is naturally formed in skeletal tissues.
Second, certain nutrients in natural products present in bone have been shown to improve the calcium absorption. For example, collagen in bone can enhance calcium absorption as shown in the in vivo 37 and in vitro experiments Calcium in the form of protein complex is also easily dissolved and released by protein digestion in the stomach rendering it ready for absorption in the small intestine.
In agreement with our previous study, fish bone calcium supplement exhibited greater bioavailability than calcium carbonate Unlike with CaCO 3 supplement, the higher fractional calcium absorption induced by tuna bone supplements did not lead to the extra absorbed calcium being excreted in the urine, but was retained to form new bone as shown by higher mineral apposition rate and bone formation marker Fig.
However, we failed to observe any difference in bone static microstructure parameters after 4-week supplementation, only dynamic change, i. Longer supplementation could have more pronounced effects on bone structure. Herein, we showed that calcium supplementation from tuna bone did not suppress 1,25 OH 2 D 3 production, nor did it compromise intestinal calcium absorption.
It further enhanced the fractional calcium absorption and mitigated negative body calcium balance as shown by the restoration of serum ionized calcium and almost all bone-related parameters to the control levels Figs.
We found a modest additive effect of calcium supplementation together with 25 OH D 3 on cortical BMD of the distal femur as compared to the effect of calcium supplementation alone Fig.
Although, 25 OH D 3 supplementation with tuna head oil increased the serum level of 25 OH D 3 , but the level of hormone 1,25 OH 2 D 3 did not change Table 2. This was possibly due to fact that calcium supplementation alone was able to effectively correct hypocalcemia so that there was no stimulator to enhance conversion of 25 OH D 3 to 1,25 OH 2 D 3.
Therefore, we did not detect any change in serum 1,25 OH 2 D 3 level in the group receiving calcium supplement with 25 OH D 3 in S3 group. Interestingly, calcium supplementation with or without 25 OH D 3 restored trabecular and cortical BMD, cortical thickness and cortical area to the normal values, but did not restore trabecular BMC, or cortical periosteal and endosteal perimeters of distal femur and midshaft femur Fig.
The mechanical properties were also restored to normal level through compensatory increases in cortical thickness and area Figs.
These findings indicate that transient inadequate calcium intake during childhood potently compromised bone accrual and bone growth in width, and these bone defects were long-lasting and could not be restored even with calcium supplementation during the period of adolescence to young adulthood.
Our results were in partial agreement with the previous study in rats which showed that low calcium intake through adolescence had a nonreversible, deleterious effect on peak bone mass, i. As mention earlier, dietary calcium intake was not directly associated with bone length, but rather controlled by a complex interaction of systemic and local factors, i.
An impairment of bone growth in width was highly significant because for bones of the same length, if one was twice as wide as the other, that bone would be eight times stronger Although calcium supplementation and the resulted increase in cortical thickness could restore bone strength to a normal level, its smaller diameter may make it more susceptible to fracture if exposed to risks brought on by inadequate calcium intake or menopause later in life.
It is well accepted that impact exercise or mechanical loading promoted osteogenesis, bone angiogenesis and increase in bone strength in both rodents and human 46 , 47 , 48 , 49 , Moreover, aerobic exercise was reported to upregulate serum 1,25 OH 2 D 3 and intestinal calcium absorption in young human and rodents 51 , 52 but was found to have no effect on calcium absorption in another human study In the present study, we found that 6 week running exercise in 6 week old rats led to a slight, but significant reduction in fractional calcium absorption when rats got to 12 weeks of age if they had received tuna bone calcium supplement, but not if they received low calcium diet.
However, this suppressive effect was not observed if running protocol continued for another 6 weeks Fig. Thus, the effect of aerobic exercise on intestinal calcium absorption varied with body calcium status and exercise duration.
We further demonstrated that voluntary running exercise increased both trabecular and cortical BMD, cortical thickness, and improved mechanical properties in low calcium intake condition, but not in adequate calcium condition Table 3 and Fig.
The benefit of exercise is usually region specific, i. In contrast, the effect of calcium supplementation is more generalized and not restricted to a particular region Herein, we used femur and tibia to evaluate the possibility of combined benefits of exercise and calcium supplementation Fig.
We found that the effect of running exercise was predominately seen on cortical-related parameters, which may be explained by the fact that exercise increased periosteal bone formation with no effect on endosteal bone formation There are games to be won, lives to change.
Coaches have the power to do both. What kind of coach do you want to be? At first glance, dietary supplements look the same. Most vitamins, minerals, fish oil, and other supplements containing nutrients are probably just fine, but supplements are not evaluated or approved by FDA before they are sold.
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At the other extreme are products that contain drugs, stimulants, anabolic steroids, or other hormones. Even though these are not technically dietary supplements, many of them are labeled as supplements.
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Weight loss products might contain prescription drugs like sibutramine, or hormones, like human chorionic gonadotropin, also known as hCG. All natural or herbal sexual enhancement products might contain hormones or Viagra-like drugs.
After all, two products might look the same, but one might contain just amino acids and other legitimate ingredients, while the other also contains anabolic steroids.
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July 1, Nutrition. How much calcium does a young athlete need? What types of foods contain calcium? Many vegetables contain smaller amounts of calcium. Examples include: 1 cup cooked spinach — milligrams of calcium 1 cup cooked kale — milligrams of calcium 1 cup cooked broccoli — 62 milligrams of calcium There are also great plant-based protein options that are naturally rich in calcium or have calcium-fortified options available.
What could a daily meal plan look like to achieve the daily recommended intake of calcium? Related Content. REDs: The Role of Nutrition in Prevention. February 1, Educators Parents. Relative Energy Deficiency in Sport—better known as REDs or RED-S—can be hard to diagnose, but essentially, it happens to athletes Read More.
Minerals are involved in a tremendous variety of metabolic and physiologic processes in the human body. In athletic performance, minerals play physiological roles in muscle contraction, normal heart rhythm, oxygen transport, antioxidant activity, bone health, and immune function.
Many of these processes are accelerated during athletic performance, so an adequate amount of these minerals is necessary for optimal performance.
Many nutritive minerals are needed for maintaining a healthy body, which helps athletes to perform at their best. However, there are certain minerals that do more of the heavy lifting in helping athletic performance, and in many cases these are minerals that are more quickly depleted during athletic performance.
These include: calcium, iron, magnesium, potassium, selenium, zinc, and sodium. The vast majority of calcium in the body is located in the skeletal system. The rest is present in other cells, such as muscle cells, including cardiac muscle.
Calcium is a key factor in the regulation of cardiac energy, and is involved in oxidative phosphorylation; a process through which the energy-rich ATP is formed in the heart and elsewhere.
Calcium also plays an important role in skeletal muscle contraction and relaxation. In a week study on young women involved in intense endurance training Dressendorfer, R, et al, Int. Sports Nut. and Exer. Calcium intake for endurance athletes needs to be adjusted upwards.
This mineral is of critical importance to anyone who exercises, and is of critical importance to athletes and endurance athletes. Magnesium is a component of more than enzymes involved in energy metabolism. Magnesium is involved in the production of adenosine triphosphate ATP from fatty acid oxidation see diagram below.
ATP stores energy and is present in all cells, especially muscle cells. Low magnesium levels can contribute to early fatigue, nausea, and muscle cramps.
Magnesium is involved in a multitude of processes that impact muscle function, including oxygen uptake and electrolyte balance, in addition to energy production. Iron is of critical importance for athletic or sports performance.
It is a component of hemoglobin, myoglobin, cytochromes, and other enzymes in the muscle cells. All of these substances are involved in the transport and metabolism of oxygen for energy required for aerobic performance during endurance exercises.
Studies have shown that athletes can experience depletion of iron [J Int Sports Nutr ; 2 1 ]. An hour of weight training can deplete 5.
Losing too much iron stores can lead to iron deficiency, which causes fatigue and saps endurance. It has also been shown that iron deficiency without anemia impairs favorable adaptation to aerobic exercise Brownlie, T. Athletes who train for 6 or more hours per week often have iron deficiency anemia and should be checked yearly for the condition.
Med Sci Sports Exer Sep; 24 9 Suppl : S ]. This mineral electrolyte is stored within muscle fibers along with glycogen. According to Jonathan Toker, Ph. It is responsible for regulating total body water, as well as stabilizing voluntary and automatic muscle contractions.
Endurance nutrition for marathoners are viewing 1 of your Flavonoids and urinary tract health free peerformance. For unlimited access take a Endurance nutrition for marathoners trial. Tom perforamnce based in the US and is a registered physical therapist with 25 years of orthopaedic and sports experience, specialising in care of endurance athletes. In addition, he has Register now to get a free Issue.Calcium and exercise performance -
The important message to athletes is to incorporate a diet adequate in calories, protein, fat, vitamins, minerals, and fluids to support the physical demands and replenish the physiologic losses incurred with physical training. The Importance of Calcium in Athletes. July 9, Breakout Magazine Recharge with Milk.
Are you motivated yet to get your daily dose of calcium? TAKE YOUR SNACK GAME TO ANOTHER LEVEL Maximize your calcium absorption by including calcium-containing recovery snacks! More News. Sodium intakes among athletes are highly variable and dependent upon taste, food choices, fitness, and level of environmental acclimatisation.
As an athlete consumes less salt, becomes more fit, and trains in the heat, sodium requirements are decreased. Overall, less is more when it comes to sodium and bone health!
Examples would include middle distance swimming or running, rowing meters, or a cycling breakaway. You should consider extensive threshold training or racing therefore as a risk factor for accelerated bone loss.
Also, because calcium is lost in sweat, requirements are significantly greater when training or racing in hot weather. Studies of athletes have estimated calcium losses via skin sweating to be in the range of mg or more per hour Cal Tiss Int.
Calculate the amount of calcium lost in sweat during a marathon, bike century, or ironman-distance triathlon, and you can appreciate why calcium requirements for athletes are so great.
Timing is everything Because calcium absorption is limited to mg or less per dose, its effectiveness will be maximised by spreading your intake throughout the day. With that being understood, there seems to be three critical times to consider: before training, during training, and at bedtime.
The experimental group was provided 1,mg of high-calcium mineral water just before and during the time trial. Like all body tissues, your skeleton is being constantly remodelled.
When blood levels of calcium decline, specialised cells osteoclasts liberate stored calcium from your bones. Osteoclasts are known to increase late at night and into the early morning hours while you sleep. Consume calcium on a sliding scale in the range of 1,, mg per day. Spread your calcium intake through the day in doses of mg or less.
Eat a diet rich in plant foods, especially fruits. Remember that threshold intensity training increases your calcium requirement and increases the risk for accelerated bone loss.
Likewise bear in mind that training or racing in hot weather increases calcium loss through sweat. Consume a calcium-rich meal or drink prior to exercise.
Consume a calcium-rich midnight snack to reduce nocturnal bone loss. Read More Bone density and muscle mass: why they matter to athletes. Cyclists: time to bone up on weight training. Energy deficiency in sport: when the quest for leanness hurts health and performance.
Related Files PPendurance-nutrition-boning-up-on-calcium. pdf PDF, 2. Tom Whipple Tom is based in the US and is a registered physical therapist with 25 years of orthopaedic and sports experience, specialising in care of endurance athletes.
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The case studies are great and it just gives me that edge when treating my own clients, giving them a better treatment. Thank you for all the work that goes into supplying this CPD resource - great stuff". Further reading Bone density and muscle mass: why they matter to athletes For endurance athletes, two of the key problems associated with getting older are a gradual decline in muscle mass and a potential loss of bone density.
The missing muscle makes it more difficult to run, cycle or swim powerfully, and the shrinking bone…. Cyclists: time to bone up on weight training Andrew Hamilton explains why ALL cyclists should include some strength training in their weekly programme.
Feel like you may have a hard time getting enough calcium from diet alone? You can also try taking a calcium supplement. There are several types of calcium supplements on the market, and choosing the right one for you is essential!
The two main forms of calcium supplements available are calcium carbonate and calcium citrate. Calcium carbonate is usually the cheaper option, but may cause some gastrointestinal upset, whereas calcium citrate is typically better tolerated.
Everybody's needs and background are different, so we suggest discussing your individual needs with your doctor. If you need additional help choosing a calcium supplement, ask your nutrition coach in the chat feature in the Vessel app! Calcium is more than just the mineral in your bones.
Be sure to include sources of calcium in your diet and try Vessel wellness cards to get personalized program recommendations to increase your Calcium levels.
What is one thing you can do today to ensure you have adequate calcium? What does Calcium do? Low calcium can be asymptomatic or result in symptoms such as: Muscle spasms Muscle cramps Weak or brittle nails Numbness or tingling in hands and feet Confusion or difficulty concentrating Easy bone fracturing Irritability Fatigue Dry skin, or other skin conditions Difficulty breathing, especially during exercise Alopecia, or loss of hair If you are concerned about your calcium levels or just want to check your levels for peace of mind, try taking the Vessel Wellness test today!
Who is at risk for low calcium? These groups include: Postmenopausal women Individuals who avoid dairy products, or those with a lactose intolerance or allergy People with a vitamin D deficiency Those with thyroid disease, or those who have had a partial thyroidectomy People with high or low magnesium levels Those with renal disease If you fall into one of these categories, it is especially important to monitor your calcium intake and calcium levels, as well as your vitamin d and magnesium levels.
How are Calcium and Sports Performance related? Calcium also affects several factors related to exercise, including: Muscle cramping during exercise Muscle gain Fatigue during exercise Risk for bone fracture during exercise Transport of oxygen during exercise Therefore, consuming enough calcium is crucial to optimize exercise performance and ensure that calcium levels are maintained during exercise to prevent any adverse impacts on bone health.
Sources of Calcium Given that calcium is so important to exercise and bone health, consuming foods rich in calcium is essential. Some of the best sources of calcium include- Dairy products, including yogurt, cottage cheese, milk, and cheese Sardines Fortified orange juice Fortified soymilk Tofu Canned salmon, with bones Soybeans Fortified cereals Greens such as spinach, turnip greens, broccolini, and kale Chia seeds Beans and lentils Figs The recommended dietary allowance RDA of calcium is mg for adult females and mg for adult males daily.
Try these meals high in calcium As mentioned earlier, having an adequate calcium intake is essential to exercise performance and maintaining healthy bones. Greek yogurt and berries They say breakfast is the best meal of the day, right?
Photo: Getty Images "], "filter": perfofmance "nextExceptions": "img, blockquote, Cwlcium, "nextContainsExceptions": "img, blockquote, a. Role of nutrition in heart health, a. Perfformance it comes Boost energy for weight loss nutrition, we Endurance nutrition for marathoners to be hearing so much about proteinfiber, vitamin D and heart-hero omega-3 fats. Yet the information cacophony on the virtues of calcium is much, much less. This is a shame when you consider how important calcium is to our health and lasting sporting performance.
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