On June 4, 2018, the Journal of the International Society of Sports Nutrition (JISSN) published an open access research article by D. AyotteJr and M. P. Corcoran, comparing the effects of a Personalized hydration plan (PHP) to a Normal (ad libitum) hydration plan (NHP).  The article reviewed previous findings in other research worth knowing.

Background:

• It is common for athletes to show up to training already dehydrated and consume inadequate fluid levels despite the ready availability of water or sports drinks [8, 11, 14, 15, 16]
• People sweat at different rates, and sodium losses are unique to individuals [8]
• losing 1–2% of body mass through sweat can yield
  • increased heart rate
  • increased core temperature
  • accelerated muscle glycogen use
  • decreases in cardiac output, cognitive awareness, anaerobic power, and time to exhaustion [2, 3, 4, 5, 6]
• Sodium is the main electrolyte lost through sweat
  • inadequate replacement can disrupt sleep and INCREASE blood pressure [7]
  • for most athletes, commercial sports drinks supply inadequate sodium [9]
• Relying on thirst signals often result in dehydration during exercise [8, 11, 13]

The Study:

• Randomized, crossover study
• Fifteen collegiate athletes
  • between 18 and 24 years of age, injury-free, able to exercise at greater than 75% of their maximal heart rate for a minimum of 45 min
  • athletes that were currently engaged in heavy, in-season, sports-specific training sessions
  • assessed for hydration habits and knowledge
• participants were assessed for sweat loss, then randomized to either a prescription hydration plan (PHP) or asked to continue with their normal hydration habits (NHP)
• Participants in each group underwent performance assessments prior, during, and immediately after a moderate to hard training session (goal average heart rate ≥ 75% of maximum for at least 45 min in duration)
• Mean and peak heart rate were recorded throughout the entire training session
• ADDITIONAL DETAILS HERE

Methods (PHP):

• A range of fluid consumption per 15 min was calculated (Min vs. Max in fl.oz) sufficient to prevent mild dehydration (2%)
• participants were advised to drink between the min and max amount of fluid at the agreed upon intervals from pre-measured bottles
• exact volumes varied from athlete to athlete
• The composition of fluid that each participant consumed for the PHP was supplemented with a level of NaCl corresponding to the participant’s sweat sodium loss

Athletic Assessments:

• Neurotracker (Spatial awareness and attention)
• Standing Long Jump (lower body anaerobic power)
• Training Session (monitoring sweat losses and HR Recovery)

Results:

Compared with pre-training performance:

• decrease in jumping distance following a NHP
• increase in jumping distance following a PHP
• PHP improved attention and awareness
• NHP did not significantly impact movement tracking, but result was negative
  

Compared with athletes' respective normal hydration plans:

• PHP improved HR Recovery significantly at both 10 & 15 min intervals, post training

Final Remarks:
So the authors of this study ultimately concluded that a PHP was effective in improving heart rate recovery, attention and awareness, and mitigating the loss in anaerobic power in collegiate athletes from various sports.

Their conclusions are supported previous research investigating the effectiveness of hydration plans against ad libitum fluid consumption.[13]

Results were not confounded by carbohydrate content of fluid replacement drinks used in the study because beverage consumption of each participant was held consistent between NHP and PHP training sessions.

"In all cases, the final [Na+] of the PHP beverages were higher than any of the sports drinks available to our athletes"

For activity lasting 120 min or less, commercial drinks are likely sufficient.  However, in this study benefits were seen in athletes who trained 70 min - 2 hours.

The authors listed some modest and understandable limitations of the study.  You can view them HERE.

Precision Hydration has offices in Vancouver and Toronto.  They can offer an Advanced Sweat Test, as well as provide pre-formulated electrolyte drink mix packets.

Other companies, like LEVELEN, offer a self-administered test that you send back for analysis.

If you are a competitive or elite level athlete, it is probably worth your time investigating the benefits of a PHP.  If you believe your recovery might be suffering due to insufficient hydration or electrolyte replacement, or you feel as though you might adhere to a hydration schedule better if you were given a prescription, then you might want to book a sweat test.

Q: I know you lift weights, but what do you do for cardio?
A: I lift weights faster
Don't let anyone convince you that "cardio" is a physical state you achieve in the absence of weights - whether it be on a bike, a treadmill, or a skipping rope.

Cardiovascular Demand VS. Oxidative Metabolism / Aerobics
Have you ever finished a challenging set of deadlifts, maybe a 5x5 at 80% 1RM, and realized that even though you took 2-min rest in between sets that your heart is now racing like a jack rabbit?  That's cardio.

Cardio doesn't mean spandex and headbands, and it doesn't mean bobbing up and down on ellipticals for 45min or more.

Cardiovascular training means placing a demand on your heart to increase its rate of contractions (HR in BPM) as well as its stroke volume (SV: amount of blood ejected by left ventricle with each contraction) in order to feed (and flush) working muscles.  Arnold constantly spoke of of "the pump", that feeling of blood-filled muscles creating pressure underneath the skin.  When you lift weights, blood is directed to the working muscles.  As you continue to lift weights (duration), or increase your pace (speed), or increase the weight (intensity/load), this demand for blood increases and SV and HR go up.  Moreover, the heavier the weight, the more mental acuity required.  This increased focus and alertness stimulates and is facilitated by increased HR.

Aerobics is essentially any activity that lasts longer than 90 seconds.  Beyond this point, oxidative phosphorylation/cellular respiration becomes the dominant energy system during continuous exercise.  As exercise duration increases, heart rate and respiration tends to increase.  In most cases, we stay at a pace where we can maintain a constant and steady rate of breathing and heartbeat. 
Engaging in this type of exercise with relative frequency is typically sufficient to improve cardio-respiratory function, mitochondrial density, and oxidative capacity.
However, adapting to exercise and seeing improvements means you have become fitter than you were, which means your aerobic training needs to be more intense to see continued improvement, or to even maintain aerobic fitness (metabolic rate may decrease as much as 5% per decade after puberty). 
By definition, the greatest demand you can place on the heart lies closest to the anaerobic threshold - the point at which the aerobic system cannot produce energy fast enough to address the energy demands placed on it.  If you've ever done interval training with a work-to-rest ratio of 1:1 or less rest, then you know what this intensity feels like.

According to a study by the Journal of Applied Physiology, a low-volume, high-intensity interval protocol of 60s:60s work-to-rest at 90% Max HR over 2-Weeks resulted in improved glucose control and metabolic health:

• reduced avg 24h blood glucose concentration
• reduced 3hr post-meal blood glucose concentration
• increased mitochondrial capacity (~20%)
• increased enzymatic activity (~227%)
• increased GLUT4 content (~369%)
  • transports glucose across muscle cell membrane

TOO MUCH, TOO LITTLE:
You don't want to be doing an hour of aerobic training each day, but then again I wouldn't advise repetitious high-intensity interval training (HIIT) each day either.  The key is balance.  You have two facets to your autonomic nervous system.  The (1) parasympathetic system is responsible for stimulation of "rest-and-digest" or "feed and breed"activities that occur when the body is at rest.  The complimentary (2) sympathetic nervous system's primary process is to stimulate the body's fight-or-flight response. 

When organizing your training it's important to schedule days that facilitate the parasympathetic response, allowing time to "rest and digest" - a Rest Day.  The term rest is relative.  Sometimes you do indeed require a day of absolutely no activity to optimize recovery.  The rest of the time you should aim to, at the very least, alternate training days of higher intensity with days of lower intensity.  It also helps to avoid stimulants (e.g. caffeine) on these days.

Example:
MON - 1hr of weight training paired with 10-15min of HIIT

TUES - 30min of Low-Intensity aerobic exercise 
WED - 1hr of weight training paired with 10-15min of HIIT
THURS - OFF
FRI - 1hr of weight training paired with 10-15min of HIIT
SAT - 30min of Low-Intensity aerobic exercise
SUN - OFF

Sources:
Low-volume high-intensity interval training reduces hyperglycemia and increases muscle mitochondrial capacity in patients with type 2 diabetes. Jonathan P. Little, Jenna B. Gillen, Michael E. Percival, Adeel Safdar, Mark A. Tarnopolsky, Zubin Punthakee, Mary E. Jung, Martin J. Gibala. Journal of Applied Physiology Dec 2011, 111 (6) 1554-1560; DOI: 10.1152/japplphysiol.00921.2011

As mentioned in the previous article:
Your bodymass directly influences your resting metabolic rate.  The more mass you have, the more calories your body needs to function.  When you lose weight, your requirement for calories decreases in tandem.  The other side of this coin is that the higher the proportion of muscle mass to fat mass you have, the more calories your body needs: the higher your metabolism.
Any weight-loss program that fails to include progressive weight-training is destined to fail long-term by not attempting to combat the reduction in metabolism due to reduction in body-mass.  Weight-training places necessary demand on the muscles to grow, or at least maintain mass.

POINT A:
So you need to weight-train, OK.  But is all weight-training hypertrophic (muscle-building)?  Yes and no.

• 50lb Goblet Squats x 50 reps will build muscle
• 100lb Barbell Squats x 40 reps will build more muscle
• 150lb Barbell Squats x 30 reps will build even more muscle

What's the reason?...the weight?  Partially.  The major factor is volume.

• 2500lbs total vol.
• 4000lbs total vol.
• 4500lbs total vol.

Even though the weight is increasing, the main determinant of your results is the total added work from example to example.

POINT B:
So squatting 150lbs x 30 reps is obviously the most effective choice here.  But if I just squat 150lbs x 30 reps two times per week for the next year, will I see steady improvement in my muscle-building?  Probably not.  Why?  

Adaptation. (click link for Basic Principles of Exercise Training)

Your body adapts to the work you do.  After 6 weeks of squatting the same weight for the same reps, your progress will have slowed or have begun to slow.  How do you combat this phenomenon on exercise physiology?

Adapt your training.  Example...
Week 1(A): 150lbs x 6 reps x 5 sets = 4500lbs
Week 2(A): 150lbs x 6 reps x 6 sets = 5400lbs
Week 3(A): 150lbs x 8 reps x 4 sets = 4800lbs
Week 4(A): 150lbs x 8 reps x 5 sets = 6000lbs
Week 1(B): 160lbs x 6 reps x 5 sets = 4800lbs
Week 2(B): 160lbs x 6 reps x 6 sets = 5760lbs

In this example, the total weight lifted progressively increases in a wavelike fashion, undulating upwards then downwards, then back up again a little higher.  This is (one form of) progressive resistance that takes advantage of the hypertrophic effects off increasing intensity/load, as well as the gradual increase in volume.  The wavelike periodization is ideal for preventing chronic maximum stress.  If going "all out" each workout you inevitably create a deficit in recovery, which impedes progress.

So even though there are many ways we may use resistance and weights in our training (see picture above), it doesn't mean that these are effective methods of muscle building or even muscle maintenance.  Because, like your caloric requirements, the stimulus required to trigger muscle growth is a moving target.  Changes in our bodyweight, our age, our environment, and even our sleeping behaviour can all affect how efficiently we build muscle.

The Journal:
Just like how you track your food, you should be tracking your training volume.  If you have someone special to create a program that is progressive by design, much of that work is done for you.  However, you should still keep a journal to make notes as to what weights are appropriate, energy level, instances of pain, any exercise modifications, or modifications based on how quickly or slowly you're progressing.

When all other variables are accounted for, calories drive fat-loss and weight-gain.

The first law of thermodynamics is an expression of the principle of conservation of energy. It states that energy can be transformed (changed from one form to another), but cannot be created or destroyed.
Our bodies take in energy (food) to perform work (measured in joules or converted to calories spent).

But as you can see, not all food calories are used to perform physical work.  Sometimes the kcal from your food is:

1. stored as energy
2. lost as heat
3. used to fuel or support metabolic reactions
4. used to fuel digestion
5. not completely digested

And then sometimes...you burn less calories for the same amount of work as you've done in the past!  Sometimes you feel like you need to put in twice as much work for the same results!

Does this mean that for some reason the first law is being broken?  That the energy going in is out of balance with the energy coming out?

No.  What it means is that YOUR BODY IS NOT A CLOSED SYSTEM, and it RESPONDS AND ADAPTS to its environment and the stresses placed on it.


A VERY IMPORTANT LESSON:
"Fat burning" and "increased metabolism" are somewhat opposing terms.  I know you've heard ads for products that claim to "stoke your metabolic fire" so you can "burn off fat".  My advice: don't waste your money.  Here's why:

1. Losing fat (and by consequence, bodymass), effectively decreases your metabolism and increases hunger cues

Your bodymass directly influences your resting metabolic rate.  The more mass you have, the more calories your body needs to function.  When you lose weight, your requirement for calories decreases.  The other side of this coin is that the higher the proportion of muscle mass to fat mass you have, the higher your metabolism.  What does this tell us?

Any weight-loss program that fails to include progressive weight-training is destined to fail long-term by not attempting to combat the reduction in metabolism due to reduction in body-mass (other social strategies and meal planning options are necessary to combat this as well).  Weight-training places necessary demand on the muscles to grow, or at least maintain mass.  One of the most crucial elements of exercise physiology that goes ignored by endurance athletes who rely solely on endurance exercise to manage their weight is that the aerobic energy system actually uses 3 fuel sources (simplified):

1. Fatty Acids (low intensity or rest)
2. Glycogen/Glucose (higher intensity)
3. Protein from deaminated muscle tissue (low or high intensity, amplified in the absence of stored carbohydrate)

Aerobics oxidize fat, but they also eat up muscle tissue.  This is generally not an issue if you eat a moderate to "high" protein diet, along with refraining from training in fasted states (glycogen depleted), and if you incorporate progressive resistance training at sufficient intensities to stimulate muscle protein synthesis (MPS).  Unfortunately, many endurance athletes I know rarely meet their minimum protein requirements, let alone that needed for athletes (1.2-1.8 g/kg bw/day).  Their A) calories are often too low and B) carb intake to high to justify the a) distances they cover and b) how low their average intensity is.  But that's a story for another time.

Bottom-line: the "fat-burning zone" is meaningless if you are overeating calories.  If your goal is to lose weight you must create a caloric deficit by consuming less calories than your body needed that day.  You can do this by eating less, or exercising more, or both.  

What you DON'T want to do is train more and more and more while eating less and less and less.  This is one form of what I call "spinning your wheels".  It's kind of the parallel equivalent of training all the time but eating whatever you want - both result in running yourself into the ground and getting nowhere fast.  Doing the former will provoke your body to adapt by lowering metabolism to deal with the excess work performed in the absence of adequate energy - a survival mechanism. 

Support your body, don't starve it.

"Energy Rules! Energy Conversion and the Laws of Thermodynamics - More About the First and Second Laws". Uwsp.edu. Retrieved 2010-09-12.

Klok, M. D., Jakobsdottir, S. and Drent, M. L. (2007), The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review. Obesity Reviews, 8: 21–34. doi:10.1111/j.1467-789X.2006.00270.x

Antonio, J., Lowery, L. M. (2012) Dietary Protein and Resistance Exercise. CRC Press, Taylor & Francis Group. 6000 Broken Sound Parkway NW, Suite 300, Boca Raton, FL

Nesheim, M., Nestle, M., (2012) Why Calories Count: From Science To Politics. University of California Press Ltd. Berkeley and Los Angeles, California.

1. Nutrient Dense Food

There are 4 criteria that we must satisfy when eating food for fitness related reasons:

• Fuel
  
• Nutrition
• Health
• Building Muscle

So how do these 4 things differ?

Fuel: we must eat enough to fuel our ability to do things we enjoy

Nutrition: we must consider the specific raw components the body requires in response to activity and where the balance lies (E.g. Endurance exercise vs. bodybuilding)

Health: is "the optimal interplay of the body's organs".  What and how much vitamins and nutrients do I need to avoid deficiencies?  What special considerations do I have (i.e. vegan, Celiac, dairy sensitivity, etc.)?

Building Muscle: you need a minimum amount of protein to avoid muscle wasting - a health related goal.  You need an optimal amount of protein to build lean muscle - a fitness related goal.

These are all slightly different criteria, but none of them can be achieved without nutrient dense food.  There are no magic foods that provide a blueprint to the perfect body, but a perfect body cannot be built out of gummy bears ;)