It is difficult to imagine comprehensive physical development, good health and a beautiful body with a weak cardiovascular system. The heart is the engine of our body, and the larger and more powerful the body, the stronger the health of the organ that pumps blood should be. Cardio training, as the main way to increase endurance, is responsible not only for the aesthetics of the body, burning fat, but also strengthens the vessels in which the blood that is already thickened from strength training flows. We will learn about what cardio should be like when gaining muscle mass in this article.
IS IT POSSIBLE TO DO CARDIO AND STILL OBSERVE FURTHER MUSCLE GROWTH?
Several decades ago, it was discovered that 10 weeks of cardio along with strength training had a negative effect on muscle growth compared to strength training alone. /1/ However, if you look at the volume of training in this study - 6 days a week cardio training and 5 days a week strength training - you can conclude that this regimen is quite difficult to stick to. Few of us will do 30 to 40 minutes of cardio six days a week.
Recent research also shows that optimal amounts of cardio can actually enhance the effects of strength training. Research has shown that strength training combined with 2-3 days of cardio can lead to greater muscle growth than strength training alone. /2,3/
What to take note from this? It seems like the sweet spot is a combination of cardio and strength training. Too much cardio can reduce muscle growth, however, at the same time, not enough cardio can limit muscle growth. Doing cardio workouts 2-3 days a week is the right choice to increase muscle mass without compromising your muscles .
Precautions for use
Using creatine as a sports supplement has a number of points to consider:
- be sure to take the drug cyclically, i.e. you should take breaks in courses;
- You should not exceed the dosage of the drug and prescribe maximum doses for yourself for the “best” effect, since the body at very high doses will stop producing creatine on its own;
- increasing the dosage leads to addiction, which hinders progress in training and strength indicators;
- do not take the drug on an empty stomach - this way you can cause indigestion and mistakenly take it for intolerance to the creatine supplement;
- pregnancy is not a strict contraindication for use, but you should definitely consult a doctor, as well as for the lactation period;
- Taking the drug at the age of 50+ may cause a slight increase in blood pressure, so women in this age group should closely monitor their health.
SEQUENCE AND DURATION OF REST
Muscular adaptations in both aerobic and strength training can potentially overlap and overlap , so it is important to allow sufficient time between workouts for rest and to optimize performance and adaptation. /4.5/
Muscle pain associated with high-intensity exercise can last up to 6 hours , so you should pause between workouts for at least that long . /2,6,7/
Conversely, if you pause too long, you may still feel muscle pain from the previous workout . This is because muscle pain has a delayed onset . Try to find a middle ground: enough rest time after the previous workout, but before the onset of muscle pain (especially after a lower body workout), which will therefore not affect the quality of your workout.
As for consistency, it doesn't always have a drastic effect on muscle growth. Several studies have examined adaptations in resistance training before aerobic training or vice versa, and found that the sequence of training had little effect on improving muscle strength and muscle growth . /8,9/
From a practical standpoint, fatigue from strength training likely have less of an impact on cardio training than the other way around. Think about it. What is better, to be tired after 3 repetitions of squats or after a 5-kilometer run? Experiment with the sequence and timing of your workouts to see what works best for you and improves your performance.
Maintaining blood glucose levels
There are two ways to maintain the required level of glucose in the blood. The first way is exogenous - the supply of glucose from outside, i.e. from the food consumed. The second way is endogenous - due to internal mechanisms associated with the synthesis of glucose and its extraction from existing reserves. The latter include gluconeogenesis and glycogenolysis. During the process of gluconeogenesis, glucose is synthesized by the body itself, in particular by the liver, from available substrates, which include free amino acids, glycerol formed during lipolysis, and products of carbohydrate metabolism, lactate and pyruvate.
Glycogenolysis is the mobilization of glycogen stored in the liver, during which the latter is converted into glucose, and it enters the blood circulation.
Both gluconeogenesis and glycogenolysis are stimulated by counterinsular hormones such as glucagon, epinephrine, norepinephrine and cortisol. An increase in the secretion of these hormones stimulates these processes, which leads to an increase in blood glucose levels. And they are held back by a hormone such as insulin. In all cases, when glucose levels rise above acceptable levels, insulin begins to suppress gluconeogenesis and glycogenolysis. This also occurs due to the consumption of foods containing carbohydrates and due to the increased secretion of contrainsular hormones.
However, the mere appearance of insulin in the blood without a concomitant increased level of glucose does not have a restraining effect on glycogenolysis and gluconeogenesis, since under conditions of insufficient levels of glucose in the blood, the secretion of the above-mentioned contrainsular hormones is activated, which in turn neutralizes hypoglycemic (as well as other related, e.g. inhibition of lipolysis) effects of insulin.
To change this situation, that is, to tip the scales towards the predominance of the inhibitory effects of insulin in the absence of hyperglycemia, is possible only by creating a super-physiological level in the blood, which is feasible only through its additional introduction into the body. In this case, the scale of action of endogenous contrainsular hormones may be insufficient to relieve the hypoglycemic effects of supraphysiological concentrations of exogenous insulin. We will encounter the phenomenon of hypoglycemia. Under natural conditions, when, for example, the concentration of insulin in the blood increases in response to the consumption of protein foods, this does not happen. Endogenous insulin levels without elevated blood glucose levels do not cause inhibition of gluconeogenesis, glycogenolysis and lipolysis, simply because these levels are within normal physiology and can be controlled by glucose homeostasis systems.
THE TYPE OF TRAINING IS IMPORTANT
Compared to other forms of cardio, running can place more strain on the muscles , most likely due to the large number of eccentric muscle contractions in the movement. Cycling, however, focuses more on concentric muscle activity.
Running for hours is probably not the best idea, but activities like cycling can improve your performance in the gym. Several studies have shown that strength training combined with cycling can increase muscle mass more than strength training combined with treadmill running or than strength training alone. /3.10/
The essence of the study
The experiment involved 30 mice who received unlimited access to food and water (hello, all inclusive). The mice were divided into three groups.
The first group of mice were content with regular food and water.
The diet of the second group was identical with one exception - 0.3% of their diet was coffee.
The diet of the third group was also no different, but the dosage of coffee was increased to 1%.
The experiment lasted a week. All three groups of mice lived under the same conditions: the temperature of their cages was constant, and their sleep-wake cycle was regulated by turning off the light every 12 hours. And yes, during the study the mice did not lift weights and were not subjected to any physical stress.
HOW TO COMBINE CARDIO AND STRENGTH TRAINING
EXAMPLE OF TRAINING PLAN 1
• Monday morning: lower body • Monday afternoon: stationary bike 8-10 sets of 1 minute, rest 1 minute. Start with a 5-minute warm-up and finish with a 5-minute cool-down. • Tuesday: upper body – press • Wednesday: rest. • Thursday morning: lower body • Thursday afternoon: stationary bike about 15 km all the time (finish 15 km as quickly as possible and aim for daily improvement) • Friday: upper body – deadlift
EXAMPLE OF TRAINING PLAN 2
• Pondelok: Vrchné partie- tlaky • Monday: upper body – press • Tuesday: upper body – deadlift • Wednesday morning: lower body • Wednesday afternoon: exercise bike 30 minutes at one pace (Try maximum intensity for 30 minutes) • Thursday: rest. • Friday: Upper Body – Press • Saturday: Upper Body – Deadlift • Sunday Morning: Lower Body • Sunday Afternoon: Rowing Machine 6-8 sets of about 400m followed by 200m recovery. (Start with a 5-minute warm-up, followed by a 5-minute cool-down)
Source bodybuilding.com
Sources:
1. Hickson, R. C. (1980). Interference of strength development by simultaneously training for strength and endurance. European Journal of Applied Physiology and Occupational Physiology, 45(2-3), 255-263. 2. Lundberg, T. R., Fernandez-Gonzalo, R., Gustafsson, T., & Tesch, P. A. (2013). Aerobic exercise does not compromise muscle hypertrophy response to short-term resistance training. Journal of Applied Physiology, 114(1), 81-89. 3. Mikkola, J., Rusko, H., Izquierdo, M., Gorostiaga, E. M., & Häkkinen, K. (2012). Neuromuscular and cardiovascular adaptations during concurrent strength and endurance training in untrained men. International Journal of Sports Medicine, 33(9), 702-710. 4. Sale, D. G., MacDougall, J. D., Jacobs, I., & Garner, S. (1990). Interaction between concurrent strength and endurance training. Journal of Applied Physiology, 68(1), 260-270. 5. Baar, K. (2014). Using molecular biology to maximize concurrent training. Sports Medicine, 44(2), 117-125. Häkkinen, K., Alen, M., Kraemer, W. J., Gorostiaga, E., Izquierdo, M., Rusko, H., … & Romu, S. (2003). Neuromuscular adaptations during concurrent strength and endurance training versus strength training. European Journal of Applied Physiology, 89(1), 42-52. 6. Bell, G. J., Petersen, S. R., Wessel, J., Bagnall, K., & Quinney, H. A. (1991). Physiological adaptations to concurrent endurance training and low velocity resistance training. International Journal of Sports Medicine, 12(4), 384-390. 7. Eklund, D., Schumann, M., Kraemer, W. J., Izquierdo, M., Taipale, R. S., & Häkkinen, K. (2016). Acute endocrine and force responses and long-term adaptations to same-session combined strength and endurance training in women. The Journal of Strength & Conditioning Research, 30(1), 164-175. 8. Cadore, E. L., Izquierdo, M., dos Santos, M. G., Martins, J. B., Lhullier, F. L. R., Pinto, R. S., … & Kruel, L. F. M. (2012). Hormonal responses to concurrent strength and endurance training with different exercise orders. The Journal of Strength & Conditioning Research, 26(12), 3281-3288. 9. Gergley, J. C. (2009). Comparison of two lower-body modes of endurance training on lower-body strength development while concurrently training. Journal of Strength & Conditioning Research, 23(3), 979-987.
Amino acids entering the blood after eating protein foods
Let's return to the topic of the article. There is no doubt that amino acids entering the blood after eating protein foods can be used as a substrate for gluconeogenesis under conditions of low blood glucose levels. This is a normal physiological phenomenon, during which amino acids unclaimed for plastic purposes are deaminated to form carbon skeletons, which in turn can be used for the synthesis of glucose. Another question is, what is the scale of this phenomenon, is it worth attaching importance to?
Before moving on to the numbers, we need to make a clarification. Amino acids enter the blood not only exogenously, that is, with food, but also endogenously in the process of natural protein metabolism. Without exception, all the protein tissues of our body are in the process of constant renewal. As a result, free amino acids are released from these tissues into the blood (several hundred grams per day). The overwhelming majority of these amino acids are included again in protein synthesis, while a smaller part is used for other purposes, according to the specific functions of each individual amino acid, including participation as a substrate for gluconeogenesis or direct oxidation in muscle cells. That is, when we talk about the fact that gluconeogenesis uses amino acids to synthesize glucose, we mean not only amino acids that come from food, but also amino acids that enter the bloodstream from protein tissues. Since in the context of this article we are concerned about the fate of amino acids taken along with protein foods, it is necessary to turn to sources that would contain information not only on the scale of use of the total amount of amino acids for the needs of gluconeogenesis, but also on the separate participation of exogenous and endogenous amino acids in this process.
2013 study “Dietary Proteins Contribute Little to Glucose Production, Even Under Optimal Gluconeogenic Conditions in Healthy Humans” (Claire Fromentin, Daniel Tomé, Françoise Nau, Laurent Flet, Catherine Luengo, Dalila Azzout-Marniche, Pascal Sanders, Gilles Fromentin, and Claire Gaudichon. Diabetes. 2013 May; 62(5): 1435–1442.)
The authors of this work specifically studied the contribution of dietary proteins to the production of glucose in humans, differentiating it from other sources. The test meal consisted of four chicken eggs (that is, 210 g of liquid whole eggs containing 23 g of protein, 19 g of fat and a negligible amount of carbohydrates). Egg whites were labeled so that the amino acids coming from them could be traced without being confused with other (endogenous) ones. Meals were taken in the morning, after a 12-hour fast. These conditions are somewhat similar to post-workout conditions, as they are associated with decreased muscle glycogen stores, as well as increased levels of cortisol and adrenaline. During the 8-hour postprandial period, blood and urine samples were collected every 30 minutes and 2 hours, respectively. Exhaled air was collected every 30 minutes and gas exchange was measured. As would be expected, 30 minutes after eating the insulin level increased (in response to protein intake), over the next 2.5 hours it remained at the same level, then began to decrease. Plasma glucagon levels tended to increase after meals and peaked at 1.5 hours. Subsequently, the concentration of glucagon in plasma did not differ significantly from the initial level. This perfectly illustrates the words said earlier that an increase in insulin concentration without a concomitant elevated glucose level is accompanied by an increase in the activity of counter-insular hormones - in this case, glucagon (it is the first to respond to fluctuations in blood glucose).
Since eating only 4 whole eggs after 12 hours of fasting and then abstaining from eating for 8 hours is clearly not enough to provide the body with energy, the body predictably extracted it from all internal resources. In contrast to proteins, the oxidation of carbohydrates and fats varied significantly during the postprandial period. The oxidation of carbohydrates increased after 2 hours, and then decreased over the course of 4 hours, while the oxidation of fats occurred almost in the opposite direction - after 2 hours it decreased, then increased all the time. Protein oxidation was constant throughout the study period. That is, the body shifted its emphasis in choosing a predominantly oxidized substrate from carbohydrates to fats, as it moved away from the time of meal. Considering that fats enter the bloodstream approximately 3 hours after consumption, this trend is partly explained by this fact. In just 8 hours after eating, 26 g of lipids and 52 g of carbohydrates were oxidized, despite the fact that a very small amount of the latter was consumed (i.e., the overwhelming majority was synthesized by the body itself). Total protein oxidation was 31 g.
What is the fate of the amino acids obtained from 4 eggs? Did they all go into the “furnace” of gluconeogenesis? After studying and analyzing all samples, it was found that of the total amount, only 18% (4.14 g) were deaminated to form carbon skeletons, which were completely oxidized within 8 hours after ingestion. Moreover, of the indicated 4.14 g, only 43% of amino acids (1.7 g), which are glucogenic, were used for the synthesis of glucose, others were oxidized in a different way (tricarboxylic acid cycle). Endogenous glucose production did not increase after meals but remained stable for 6 hours and then fell.
Of the 50 g of glucose produced by the liver over an 8-hour period, 8-14 g (8% of total glucose) were synthesized from all amino acids (exogenous and endogenous), of which only 4 g were synthesized from food amino acids (2% of total amount of glucose). 2-3 g of glucose was synthesized from glycerol and 34-40 g (70%) from liver glycogen due to glycogenolysis. Despite the 12-hour fasting period, the glycogen stores in the liver were not completely depleted. The fact that the night period does not lead to a complete decrease in hepatic glycogen is confirmed by other studies. In general, this is normal, given that cells do not feed on glucose alone. In fact, gluconeogenesis itself was not the main pathway for the appearance of glucose in the blood; its share in this was approximately 20%. However, during a longer fast and after the glycogen reserves in the liver are depleted (training does not lead to this), the rate of gluconeogenesis and the use of amino acids for its needs will be higher.
The authors also noted that all deaminated amino acids were oxidized within the studied 8 hours after food intake, while after 4 hours only half of them were used as an energy substrate. Thus, 4.14 g of deaminated amino acids from whole eggs provided the body with energy for as much as 8 hours. This is a negligibly slow rate of amino acid utilization, averaging 0.5 g/hour. The authors suggest that the utilization of carbon skeletons in energy pathways is delayed after the deamination process due to saturation of carbon cycles and insufficient energy storage of these substrates. In simple terms: the rate of production of carbon skeletons exceeded the rate of their use as an energy source.
Amino acid losses obtained from egg whites (18% of intake) are comparable to losses observed after ingestion of milk proteins in other studies
(Postprandial kinetics of dietary amino acids are the main determinant of their metabolism after soy or milk protein ingestion in humans. Bos C, Metges CC, Gaudichon C, Petzke KJ, Pueyo ME, Morens C, Everwand J, Benamouzig R, Tomé D. J Nutr 2003 May;133(5):1308-15. Compared with casein or total milk protein, digestion of milk soluble proteins is too rapid to sustain the anabolic postprandial amino acid requirement. Lacroix M, Bos C, Léonil J, Airinei G, Luengo C, Daré S, Benamouzig R, Fouillet H, Fauquant J, Tomé D, Gaudichon C. Am J Clin Nutr. 2006 Nov;84(5):1070-9.)
As we see, not all of the consumed protein went into the firebox, but only less than a fifth of it. But at the same time, endogenous amino acids were also used for energy needs. However, even these modest numbers were obtained within an 8-hour interval after consumption of food. In practice, given the common frequency of nutrition in sports, such long intervals are unlikely. Although 16-hour periods without food, when consuming the planned macro (KBZHU) in the remaining 8 hours in the day, do not lead to any protein catabolism and do not interfere with the growth of bodybuilders’ athletic performance.
(Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. Tatiana Moro, Grant Tinsley, Antonino Bianco, Giuseppe Marcolin, Quirico Francesco Pacelli, Giuseppe Battaglia, Antonio Palma, Paulo Gentil, Marco Neri and Antonio Paolicorresponding J Transl Med 2016;14:290 Time-restricted feeding plus resistance training in active females: a randomized trial Tinsley GM, Moore ML, Graybeal AJ , Paoli A, Kim Y, Gonzales JU, Harry JR, VanDusseldorp TA, Kennedy DN, Cruz MR. Am J Clin Nutr. 2022 Jul 3. pii: nqz126.)
The scale of glucose synthesis from amino acids is very revealingly demonstrated by one of the earliest works on this topic (1936)
Let's look at the drawing. The graphs compare changes in blood sugar levels after consuming either glucose (solid line) or protein (dashed line) on an empty stomach:
1 schedule: 80 grams of glucose and 160 grams of protein (from a mixture of lean meat, egg whites and casein)
Schedule 2: 66 grams of glucose and 132 grams of protein (from lean meat)
What are we observing? In both cases, after consuming glucose, the sugar level rapidly increases and by the end of the second hour falls, and below the initial level. Then it normalizes (thanks to counter-insular hormones).
After consuming an impressive dose of protein, sugar levels fluctuate slightly around the initial level for 4 hours. High doses of protein were used deliberately to create an apparent excess of amino acids that would exceed their utilization by the intestines, liver and muscle tissue. In this case, the excess should potentially be used for energy needs, incl. through gluconeogenesis. However, gluconeogenesis, as can be seen from the graphs, remained stable and, over a controlled period of time, only ensured a normal level of glucose in the blood. There is no massive “conversion of protein into energy” observed here.
The above results of the two studies, despite the impressive difference between the time they were conducted - almost 80 years, show one general picture. The synthesis of glucose from amino acids entering the body with food is not a large-scale process. Any physiological phenomenon, any reaction, has a limited speed of implementation. Muscles do not grow at the rate of one kilogram per day, even the fastest carbohydrates are not absorbed in a few seconds, glycogen is not synthesized in full in an hour, no matter how we eat, and not a single person has run a hundred meters in less than 9 seconds. There are limits to everything. There are many reasons for the limited rate of gluconeogenesis; listing them is not the scope of this article, but one very original reason, closely related to protein consumption, deserves mention: “Changes in the concentration of circulating amino acids modulate metabolic processes in the liver through sensory mechanisms located in the central nervous system. Sensory mechanisms that modify hepatic carbohydrate metabolism...respond to the increased availability of various amino acids such as leucine, proline, histidine, and possibly several others, reducing hepatic glucose production through decreased gluconeogenesis and glycogenolysis." The increase in amino acids in the blood itself, caused incl. Eating protein foods inhibits gluconeogenesis and even glycogenolysis. [The Role of Circulating Amino Acids in the Hypothalamic Regulation of Liver Glucose Metabolism. Isabel Arrieta-Cruz and Roger Gutiérrez-Juárez, Adv Nutr. July 2016; 7(4): 790S–797S]
Interestingly, even in individuals with carbohydrate metabolism disorders, a similar picture is recorded. In a study examining the effect of protein intake on blood glucose levels in people with type 2 diabetes, it was found that after fasting 50 g of protein from very lean beef, there was an increase in circulating insulin, glucagon (as in the first study reviewed), and the amount glucose appearing in the bloodstream within 8 hours after eating was only about 2 g more than after drinking water under the same conditions, by the same people.
Does creatine cause baldness?
Not long ago, there were rumors that creatine helps increase levels of dihydrotestosterone, a more powerful androgen that is involved in energy production (good), and also contributes to hair loss in certain categories of men and the development of prostate cancer (bad). Those with plenty of hair on their heads need not worry about an increase in dihydrotestosterone levels, but people prone to baldness may actually feel the rate of baldness increase when taking creatine supplements. At the same time, speaking about baldness and its connection with creatine supplements, it is worth noting that no clinical studies have been conducted on this topic. And even though dihydrotestosterone itself is the enemy of hair follicles, creatine accumulated in them in this situation performs a protective cellular function. The specific effect of creatine supplements on men prone to hair loss has not been studied.
It is logical to assume that creatine negatively affects the rate of baldness, but how and how negatively is unclear.
