Maximizing Muscle Retention While in Caloric Deficit
Lose Fat, Keep Muscle
Slow and Steady Wins the Gainz Race
One of the biggest misconceptions of what an optimal diet looks like is the need to drastically reduce calories or increase cardio from the very beginning.
At first glance, it would make sense that the greater change made, the greater the weight loss that would follow. Although doing this would, in fact, incite a larger, quicker weight loss - what should be noted is that a much larger percentage of that weight loss will likely be from muscle tissue and not body fat.
The phrase "slow and steady wins the race" proves true once again when it comes to weight loss. Generally, a good rule of thumb is to aim for a maximum of 1-2lbs of weight loss per week. Making an effort to remain within this range will go a long way in ensuring that the weight lost is from body fat, and a much lesser degree of hard-earned muscle tissue.
Drastic weight loss can also greatly increase the rate of metabolic adaption, which can make it increasingly difficult to lose weight in subsequent weeks and months. Following a more gradual diet can help to minimize adaptations to your metabolic rate and lead to greater success over the course of a dieting phase. 
Perform Cardio on Leg DaysA tip I picked up a few years ago from mentor and fellow prep coach, Cliff Wilson, is to implement the initial cardio sessions only on leg days. Since many of us already train legs multiple times each week to maximize growth, if we were to start by performing cardio on days other than our leg workouts - it could reduce the ability to recover between leg workouts, and hinder our ability to maintain necessary strength output and intensity.
At some point cardio will likely have to be performed multiple days each week, leaving us to do it not only on leg days but at other times during the week as well. At that point there isn't really much that can be done to avoid it, but in the initial stages of a diet, when we're only performing 1-2 cardio sessions each week, putting them at the end of leg workouts can be a huge help for a lot of athletes already training legs with a lot of intensity.
Generally I train legs twice each week; so when I eventually begin adding cardio to my diet programming, I'll first add a session to my lower rep focused training session since at that point I've already been pushing myself extremely hard with all the squats and deadlifts, so mentally I feel more inclined to go ahead and knock out a HIIT cardio session before hitting the showers.
As I add another cardio session I will then put it at the end of my other leg workout of the week. At this point, I've added two cardio sessions that can be great for spurring more fat loss, but am still allowing myself a full 2-3 days between each session to allow my legs to recover as much as possible.
Not only have I noticed this help myself and other clients to better mentally deal with the addition of cardio, but also stay fresh for longer during a diet- leading to better strength during workouts and a greater likelihood of preserving strength and muscle tissue while losing body fat.
It should be noted that another option would be to use exercises like battle ropes as HIIT cardio in order to reduce the total workload placed on the lower body during a given week. Placing a HIIT cardio session at the end of an upper body workout, and completing several rounds of battle rope swing intervals can be a great cardiovascular workout while reducing lower body fatigue; not to mention providing a mental break from the constant treadmill and spin bike sessions.
Don't Change Training IntensitySpeaking of maintaining strength when dieting, this brings me to the next very important point athletes should consider when dieting - their weight training programming.
Unfortunately, the old myth that athletes should begin training with lighter weight and higher reps when they begin dieting in order to burn more calories and lose fat more effectively still hangs around the fitness industry like a bad cold. The truth is, this is one of the very last things we as physique athletes want to do as we turn our focus to fat loss.
Muscle tissue is one of the most metabolically expensive tissues our bodies have to maintain. This is one reason why it's so difficult to gain and maintain muscle throughout life. it's hard enough to gain muscle when food intake is sufficient and recovery is at its best.
Start taking away food otherwise used for energy and maintaining muscle tissue, and adding in cardio that, although helpful in fat loss, can impair overall recovery - and that maintenance expense for your muscle tissue becomes increasingly less likely to be paid by the now strapped for cash body.
Despite restricting food and adding cardio, we can still greatly influence muscle retention by continuing to train hard and heavy. The continued demand on the muscular system prompts the retention of muscle tissue to a greater degree as our bodies attempt to continue adapting to stress placed on them through intense training.
When we instead begin letting up on the gas and training with lighter, less challenging loads, we essentially lower the need for our bodies to maintain the expensive tissue and create a greater likelihood of the now unnecessary muscle tissue to be 'thrown away' by the struggling body.
The truth is, resistance training programs shouldn't change very much from what we were doing during the off-season. Training in a variety of rep ranges, hitting each major muscle group multiple times each week, and training with loads as heavy as we can for the prescribed rep range are all vital for not only growing muscle tissue, but for also retaining it when dieting.
Make sure to continue including a variety of multi-joint exercises in order to stimulate as many muscle fibers as possible, and allow for sufficient overload of the muscles. Variations of the squats, deadlift, and various presses can and should form the foundation of each training program.
As an additional note, I also believe simply maintaining the right mindset in our approach to training sessions while dieting can go a long way in helping us maximize our muscle retention. As a diet progresses, it can become more and more difficult to feel energetic and excited heading into a workout.
As this happens, it can be more difficult to approach each set with the necessary intensity. Knowing this ahead of time, taking steps to mentally prepare ourselves for each workout, and to approach the session with the understanding that the intensity we display each workout is vital in the retention of that hard earned muscle can go a long way in helping to maintain the muscle tissue we've worked so hard for while losing the body fat we can't wait to be rid of.
Keep Protein Intake HighThis may seem a bit counter-intuitive since a diet normally means lowering food, not keeping it the same. However, I believe protein intake is one exception. For the majority of athletes, protein should remain largely unchanged throughout a diet- lowering protein only slightly near the end of prep if more calories need to be removed and carbs and fats are already quite low.
Otherwise, whatever my client's protein intake is at the start of a diet, I make an effort to keep that level constant and instead make the large majority of reductions from carbohydrate and fat intake. In addition to some solid research highlighting the benefit of high protein intakes while dieting, I've also seen it be of great benefit personally in the athletes that I've worked with. 
Muscle Saving SupplementationMost people that begin a diet and are visiting a supplement website first check out the fat loss products section. Although that would seem like the first logical step, it may actually be more prudent to first implement products that are designed to help with muscle retention and recovery.
My reasoning for suggesting this is because when most people begin a diet, they do so with the intent to achieve a leaner, more muscular and shapely physique. If someone is to lose a bunch of weight without paying attention to muscle retention, they'll instead end up with a stringy, lanky appearance and not the full, well-shaped physique they originally had in mind.
With that said, after a diet is in place and protein intake is sufficient; a consistent training program is in place with plenty of multi-joint movements included and training intensity kept high, and cardio is being implemented as strategically as possible, dieters can greatly benefit from a quality branched chain amino acid (BCAA) and HMB (otherwise known as a Hydroxy -Methylbutyrate) product.
BCAAs are shown time and again to help with muscle retention during the offseason as well as when dieting by supplying muscle with the amino acids leucine, isoleucine and valine. Ensuring an optimal supply of these amino acids contributes to better performance during workouts by providing a secondary energy source for muscle tissue as glycogen and circulating blood glucose are depleted.
This reduces the likelihood that muscle tissue and amino acids within the tissue are used as the back-up energy during intense training. This, in turn, leads to better gym performance and better retention of muscle tissue during intense exercise. it's also believed the sufficient BCAAs will prevent premature fatigue by reducing the uptake of tryptophan within the brain that would otherwise promote the production of serotonin, a hormone that signals sleepiness and fatigue. 
In terms of what BCAA product to purchase, there are a few things in particular that I really stress for athletes to consider. The first is that they choose a brand that doesn't use proprietary blends. By including a prop blend, a brand is essentially hiding information about what amount of each ingredient they are using in order to not highlight the fact they are likely trying to cut costs by skimping on expensive ingredients, and loading up on the cheap stuff.
If you're spending your hard earned money, you deserve to know exactly what you're paying for. For this reason, I always encourage clients to research and purchase a product that provides full disclosure on their labels.
A second consideration I suggest is to purchase a brand that uses a 2:1:1 ratio of leucine, isoleucine and valine, respectively. it's become common practice for brands to provide products with 6:1:1 or even as much as a 10:1:1 ratio.
A major issue I have with this is that nearly all research showing benefit from BCAA consumption are on 2:1:1 ratio servings, meaning that you're most likely to benefit from a product using that ratio as well. Higher ratios are actually thought to be less effective due to the unbalanced ratio that may lead to amino acids competing with each other and not leading to as effective of protein synthesis promotion.
For these reasons, I encourage clients to look into Core ABC as their amino acid product. Each serving of Core ABC contains 10 grams of BCAAs in the supported 2:1:1 ratio, and also includes beta-alanine, citrulline malate and L-glutamine to further aid in better endurance and recovery.
To top it off, the label provides full disclosure, allowing customers to see exactly what they are paying for.
How Much to Take: Although realistically it would be virtually impossible for a healthy adult to consume too many BCAAs, we all of course want to make sure we aren't wasting hard earned money by taking more than necessary for optimal benefits.
Since many of the benefits of BCAA consumption are shown to be realized during training, I like to suggest clients start with 7-10g during their workouts. As an individual's budget allows, I then suggest considering an additional 3-5g between meals during the day to ensure sufficient protein synthesis throughout the day.
HMB (Hydroxy - Methylbutyrate)
HMB has gained more popularity in recent years as research continues to emerge in various clinical settings, and more recently in athletic populations, to show its potential benefit to reducing muscle loss. It's believed that HMB's benefits come less from its promotion of muscle growth through enhanced protein synthesis and more through the reduction in muscle loss by lowering protein catabolism - resulting in a greater net protein synthesis (think of making the same salary but reducing monthly expenses).
Although it may be beneficial to take year round, the available research makes it very likely to be helpful while dieting when protein catabolism can be accelerated. Since HMB is a metabolite of the amino acid Leucine, which is vital in promoting protein synthesis, the two serve as a '1-2 punch' for muscle retention and maximizing the effectiveness of a diet.
How Much to Take: The general suggestion is 1-3 (1g) servings spread throughout the day, with one serving being taken 30-45 minutes prior to exercise.
Saved Gainz are the Best Gainz
Even though Popeye only needs a can of spinach to get jacked, we need a little more than that to reach our goals. We all work extremely hard every day, for weeks, months and years on end to achieve the muscle growth and gym performance we've long dreamed of.
After putting in so much work, losing some of that progress through sub-optimal dieting shouldn't even be an option. Keeping these strategies in mind can help athletes hold onto the physique they have built while losing the body fat needed to unveil all their hard work.
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2) Doucet, E., St-Pierre, S., Alméras, N., Després, J., Bouchard, C., & Tremblay, A. (2001). Evidence for the existence of adaptive thermogenesis during weight loss. BJN British Journal of Nutrition, 85(06), 715. doi:10.1079/bjn2001348
2) Garthe, I., Raastad, T., Refsnes, P. E., & Sundgot-Borgen, J. (2010). Long-term Effect Of Two Different Weight Loss Interventions On Changes In Body Composition And Performance. Medicine & Science in Sports & Exercise, 42, 17. doi:10.1249/01.mss.0000384496.11401.ee
4) Mettler, S., Mitchell, N., & Tipton, K. D. (2010). Increased Protein Intake Reduces Lean Body Mass Loss during Weight Loss in Athletes. Medicine & Science in Sports & Exercise, 42(2), 326-337. doi:10.1249/mss.0b013e3181b2ef8e
5) Blomstrand, E. (2011). Branched-Chain Amino Acids and Central Fatigue: Implications for Diet and Behavior. Handbook of Behavior, Food and Nutrition, 865-877. doi:10.1007/978-0-387-92271-3_57