Protein: its under-appreciated role in Optimal-Active Aging (Part II)
by Joseph Jimenez, M.D., MBA, CSCS, and Hector Lopez, M.D., CSCS, CFT.
In the first article (Part I), protein was established as the chief component of a preventive and therapeutic nutritional
intervention plan for optimal-active aging. Additionally, we explored the presentation, epidemiology,
and major players responsible for initiating, maintaining, and exacerbating sarcopenia and syndromes of disordered
body composition. The vicious sarcopenic cycle involves: loss of functional skeletal muscle—decreased
responsiveness to hormonal and nutritional stimuli—further loss of muscle mass—further decline in physical
activity, functional capacity, and mobility. This installment will focus on integrating protein intake, strategic
supplementation, nutrient timing and exercise to yield a rational approach to aging optimally.
Essential Amino Acids are just that…Essential to
Skeletal Muscle and Protein Status
Amino acids are the building blocks of the protein. Essential
amino acids (EAA) are those amino acids that need to be obtained
through diet and cannot be made by the body in suf-
ficient quantities. Those amino acids that can be synthesized
within the body and don’t need to be obtained from the diet
are termed nonessential amino acids (NEAA). The eight essential
amino acids including leucine, isoleucine, valine, lysine,
phenylalanine, tryptophan, methionine, and threonine are considered
the anabolic nutrients that induce protein synthesis in
human muscle. Furthermore, the elderly seem to be just as responsive
to the anabolic effects of EAA supplementation, when
compared with much younger age groups. It is also clear that a
reason why high carbohydrate and low protein diets have failed
to promote protein synthesis in the elderly is because of insuf-
ficient concentration of EAA content in such diets. Moreover,
the decreased glucose tolerance and insulin sensitivity which
accompanies sarcopenia in the senior population, along with
negative energy balance creates a sate of pronounced muscle
catabolism. Essential amino acids may provide a viable method
of circumventing the dilemmas of negative energy balance and
insulin resistance. EAA supplementation alone is sufficient to
induce protein synthesis providing caloric intake is adequate.
There is a body of literature suggesting the elderly have a unique
“selective” insulin resistance. Specifically, there appears to be
a blunted protein synthesis to insulin in old age. Two potential
mechanisms for this observation of selective insulin resistance
include: 1) blunted molecular signaling for muscle protein synthesis;
and 2) diminished nitric oxide induced vasodilatation
(blood flow) causing a decrease in amino acid delivery to muscle.
In fact, there is scientific data to suggest that insulin may
impair the anabolic response of muscle to EAA in the elderly.
Hence, essential aminos provide a more efficient avenue for the
aging individual to work around the potential roadblock created
by this “selective” insulin resistance observed in the geriatric
population. Studies also indicate that a subgroup of essential
amino acids known as the branched-chain amino acids (BCAA)
is particularly useful in the proper clinical setting for inhibiting
excess muscle catabolism and promoting positive nitrogen
balance. More recently, the amino acid L-leucine has received
great interest in the scientific and clinical world for its ability to
induce protein synthesis directly, and amplify key anabolic signals
within skeletal muscle. Leucine’s downstream metabolites,
hydroxyl-methyl butyrate (HMB) and keto-isocaproate (KIC) may
play supportive roles in slowing the progression of sarcopenia.
Here are some recommendations regarding EAA:
- Supplement your diet with at least 10 grams of free form EAA (that is not bonded together molecularly to form longer peptide chains of protein) a day to help build functional muscle mass and strength, by inducing muscle protein anabolism (providing caloric intake is adequate).
- Supplementing your diet with 10–30 grams of free form BCAA can help maintain lean body mass, by potentiating insulin signaling and other aspects of the muscle’s anabolic machinery.
- The doses, timing and frequency of intake mentioned above may vary considerably according to the individual’s need from diet, activity, training and medical history.
When there’s a will there’s…..Whey (protein)
Whey protein is a milk derived protein found in most protein
powders. Whey protein is a high quality protein rich in EAA and
BCAA. In fact, many of the anabolic attributes of whey protein
are due to its high concentration of EAA when compared to other
proteins such as meats and vegetable-derived proteins.
Another important characteristic of whey is the kinetics or
speed of absorption and assimilation. Whey protein is considered
a “fast protein”; i.e., it is immediately soluble in the digestive
tract, quickly digested, and its constituent amino acids
are rapidly and transiently absorbed into the bloodstream. This
pattern of a transient rise in amino acid concentration in blood
plasma is associated with protein synthesis in humans (i.e.,
anabolic properties). In this respect, whey protein is a very costeffective
way of increasing calories (to maintain positive energy
balance) and providing an anabolic stimulus. Moreover, the
combination of calcium supplementation with whey protein as
part of a healthy protein-emphasized diet may help improve or
preserve lean body mass, decrease body fat through enhanced
metabolic health and hence abate dysfunctional metabolic syndromes.
Another protein source rich in EAA, in particular, methionine,
glutamine and arginine (conditionally essential) is soy protein.
Soy protein has been used successfully in small studies to enhance
recovery from exercise. Finally, another protein source
that is worthy of mention is casein; also a milk-based protein
that in contrast to whey, is considered a “slow protein” because
its coagulation in the digestive tract slows absorption. As such,
it leads to steady levels of amino acids trickling into the bloodstream
and attenuating protein breakdown (i.e., anti-catabolic
properties).
Here are recommendations with regards
to protein supplementation:
- Supplementing your diet with a combination of 15–40 grams of whey protein, and/or 6-30 grams of casein is a safe way to increase daily caloric and protein intake. Nutrient density as opposed to energetic/caloric density becomes more critical in older age. Protein and EAA are an even more efficient, high-yield component of the elderly’s diet due to the decline in appetite and food intake that parallels aging.
- Adding calcium, EAA and/or BCAA with your whey protein or soy protein, and casein supplement will help build and preserve lean muscle tissue, while providing the structural building blocks for improving bone health.
- Combining your favorite whey/casein protein shake with 15–35 grams of a high-fiber and minimally processed carbohydrate source such as: oats, beans/legumes, whole grain pasta, whole grain/wild rice, barely, whole grain bread, fruits/veggies, or “green-food” supplements with 3–8 grams of mono/polyunsaturated fats (omega-9 MuFA/omega-3 PuFA) is a great way to prepare a meal replacement to displace unhealthy snacks or meals.
PREvent dysfunctional aging and sarcopenia
with PRE (progressive resistance exercise)
Strength training or resistance exercise is the preferred method
of exercise to prevent and treat the clinical effects of sarcopenia,
osteoperosis, and it even addresses the problems of glucose
intolerance/diabetes, and obesity that characterize the
dysfunctional metabolic state associated with sarcopenia and
aging. The classic view of exercise in the medical field was the
emphasis of aerobic exercise for cardiovascular and general
health benefits. Although it is true that aerobic training specifi-
cally increases aerobic fitness and endurance, it does not address
the specific needs of strength and power development for
optimal performance of most daily personal, higher-level, work
and recreational activities. After all, the decrement in strength,
power and endurance that accompanies sarcopenia are most
detrimental to disability and quality of life. More recent studies
also show that resistance training improves metabolic health,
body composition, and even cardiovascular health, such as hypertension
—a benefit traditionally attributed almost exclusively
to aerobic exercise. There is also preliminary evidence to suggest
that the metabolic benefits specific to PRE may improve
longevity. Another important point is that gains in muscle
strength and hypertrophy, as well as metabolic/cardiovascular
health benefits occur in as little as 3–6 weeks for both men and
women, even as old as 90 years of age. Finally, compliance to
such programs (in the proper setting) was as high as 80–90
percent. Clinically, the combination of aerobic and progressive
resistance exercise is ideal for optimal functioning, quality of
life, aging, and health. The bottom line: PRE is the most effective
single, long-term intervention for attenuating and/or preventing
sarcopenia.
Some general recommendations regarding exercise:
- Always check with your physician before starting any exercise program.
- A base-level progressive resistance exercise (PRE) program could be 2–3 days a week for 20–45 minutes and working anywhere from 4–8 body parts per day. It would be optimal for most to be under the guidance of a qualified fitness professional to choose the appropriate resistance and exercise technique. A good starting point would be to choose a weight that is 50–60 percent of your theoretical 1-rep max (RM), i.e. if a weight can theoretically allow you to perform only one rep in proper form… this is your 1RM. Therefore, 50 percent of this weight is known as “50 percent of your 1RM”. Over the course of 3–4 weeks, the weight is progressively increased so that you’ll be lifting up to 80–90 percent (on occasion) of your 1RM in good technique. This general model has been shown effective even in men and women ages 60 to 90 years of age. Most persons would benefit greatly from being in the hands of a qualified professional, who would “periodize” or cycle the training parameters. Periodization is effective not only for maximizing recovery, long-term gains and adaptation, but also for preventing boredom or staleness in any strength-training regimen.
- In addition to PRE, take your new found strength and perform aerobic activity (at both multiple levels of intensity) for 2–3 days a week (comprised of walking, running, or favorite sporting activity) for 15–45 minutes a day.
- For patients living with hypertension and cardiovascular disease, PRE is not only safe but should be an adjunct to aerobic exercise. The combination of exercise modalities is more effective than aerobic exercise alone.
Integration is the best medicine
The strategic timing of nutrient consumption around the exercise
and recovery periods may be the best approach to prevent,
abate, and naturally treat sarcopenia. We have introduced the
importance of protein in the diet as well options for supplementation
that seem to have positive effects on aging muscle
independent of exercise. Numerous studies on the benefits of
exercise on aging muscle independent of any specific dietary
intervention have also been demonstrated. The combination
of exercise and optimal nutrition is still the best recommendation.
More specifically, exercise induces a metabolic state where
the body is more receptive to the anabolic effects of nutritional
intervention [nutrient timing (Chrono-Nutrtion™), protein and
amino acid supplementation]. Muscles seem most receptive
in the “peri-workout” period, i.e., the period immediately surrounding
exercise (before, during, and up to 2–4 hours after
exercise).
General guidelines with optimal timing
of nutrient consumption:
- About 2–3 hours before PRE, consume a balanced whole-food meal with low to moderate glycemic index carbohydrate with 10–30 grams of lean protein. Then 10–15 minutes before PRE, consume 6–10g of EAA (with or without small amount of moderate to high glycemic carbohydrate; e.g. sports drink).
- During any PRE or intense aerobic activity, consume a 10–20 gram BCAA drink/supplement (optional: mix within a dilute 3–6 percent sports drink, carbohydrate-electrolyte or carb-electrolyte- protein beverage).
- Immediately after every PRE, take 10–25 grams of whey protein supplement (or other fast-acting protein) mixed with 10–25 grams of carbohydrate drink and 5–8 grams of EAA/BCAA.
- Within 2 hours after exercise, consume a balanced whole food meal with moderate glycemic index/load carbohydrate, high quality protein, and functional fats (MuFA and omega-3 PuFA).
- Within 4 hours after exercise, consume another 15–25 grams mixture whey/casein/soy protein enhanced with 5–8 grams of EAA/BCAA to optimize and maintain protein anabolism.
As mentioned at the beginning of the article, the battle against
sarcopenia and dysfunctional metabolic syndrome starts with
a healthy nutritional lifestyle focusing on adequate protein intake,
moderate carbohydrate intake, and a daily dose of healthy
fats. A healthy nutritional platform provides an optimal metabolic
springboard to increase physical activity/exercise safely
and effectively. Finally, the rational use of dietary supplements
(Rational Poly-supplementation™), in the setting of Chrono-
Nutrition™ (nutrient timing) will not only enhance their utility,
but also act synergistically with exercise to maintain active aging,
health and wellness.
For references send a SASE to totalhealth magazine.
Joseph Jimenez, M.D., MBA, CSCS and Hector Lopez, M.D.,
MS(c),CSCS are physicians trained in the specialty of Physical
Medicine and Rehabilitation. They are co-founders of Physicians
Pioneering Performance*, LLCTM. PPP is a multi-specialty, interdisciplinary
group of like-minded doctors who seek to seamlessly
integrate musculoskeletal, spine and sports medicine, optimal
aging, and rehabilitation, with medical and performance
nutrition, athletic performance, and fitness to accommodate
the needs of a diverse population. The PPP group has an interest
in developing a new paradigm of rehab medicine…“Integrative/
Metabolic Physiatry” through strategic, rational nutritional and
metabolic intervention as another “tool” in the armamentarium
to enhance functional/performance outcomes in patients,
healthy laypersons, and athletes alike. PPP is collaborating with
MyoTrend Nutritional Technologies (MNT) to educate and empower
consumers in performance nutrition science and safety.
The alliance with MNT seeks to bring forth supplements that
have long-lasting value, and embody a true balance between
the best appraisal of the available scientific evidence, and innovation
through out-of-the-box thinking. Research interests of
PPP include: 1) Applying advances in sports nutrition and exercise
science to enhance the functional capacity and human/
athletic performance of the rehabilitation patient population,
athletes, and laypersons; 2) Nutritional and training strategies
to improve health and performance of elite athletes, obese patients,
able-bodied laypersons, and senior/aging population.
*“PPP-Physicians optimizing athletic performance in sport…
and human performance in day to day life for athletes, patients,
and laypersons alike.”
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