Isotonic Drinks & Gels: The Stacking Foundation
Isotonic drinks and gels share a core function: they deliver carbohydrates and electrolytes in a concentration close to body fluids, supporting hydration and energy availability during prolonged or intense exercise. Products such as OstroVit Isotonic Drink 1500g Pirn, OstroVit Isotonic 500g Apelsin, PowerBar Iso Active 600g Sidrun, PowerBar Iso Active 600g Punased puuviljad, and PowerBar Iso Active 600g Apelsin are formulated to be effective as standalone intra-workout support. The question is what to add — and what to keep separate.
Browse the range at /en/category/isotoonilised-joogid-ja-geelid.
Evidence-Based Synergies
Caffeine is the most evidence-supported addition to any isotonic-based intra-workout protocol. A meta-analysis confirmed that caffeine improves endurance performance in trained athletes (Doherty & Smith, 2005). Caffeine is often found in pre-workout products and some energy gels. If your isotonic drink does not contain caffeine, adding a separate caffeine product before exercise is a logical stack.
Multiple transportable carbohydrates: Isotonic drinks typically use glucose or maltodextrin. Stacking with a gel that uses a fructose-glucose combination (e.g., a 2:1 maltodextrin-to-fructose ratio) can increase total carbohydrate absorption beyond what a single transporter allows during prolonged events — relevant for endurance sessions exceeding 90 minutes (Jeukendrup, 2010).
Sodium and electrolytes: Most isotonic drinks contain sodium, potassium, and sometimes magnesium. If your session lasts over 90 minutes or you are a heavy sweater, supplementing with additional electrolytes such as OstroVit Electrolyte 90tabs alongside your isotonic drink can reduce the risk of hyponatraemia and cramping.
Antagonistic Combinations
High-protein shakes during exercise: Adding a full protein shake to your intra-workout isotonic protocol slows gastric emptying and can cause gastrointestinal discomfort during high-intensity effort. Save protein intake for the post-workout window.
Fat-heavy foods alongside gels: Energy gels are absorbed rapidly because they contain minimal fat. Eating a fatty snack around the same time slows absorption — defeating the purpose of a fast-acting gel during a race or intense training session.
Concentrated hypertonic solutions: Mixing two isotonic products together into a smaller volume of water creates a hypertonic solution that draws water into the gut and can worsen dehydration and nausea. Always follow the manufacturer's recommended dilution.
High-dose creatine intra-workout: Creatine is best taken around workouts but does not need to be mixed into your isotonic drink. Creatine monohydrate is stable in solution for a short time, but mixing it into an acidic isotonic drink before a long session may slightly degrade it. Take creatine separately or with a plain water rinse.
Timing within a Stack
- 60–90 minutes before: Pre-workout or caffeine, light carbohydrates from food.
- Start of session: Begin isotonic drink sipping at the outset for sessions over 45 minutes.
- Every 20–30 minutes during session: Alternate sips of isotonic drink. For sessions over 75 minutes, add a gel every 30–45 minutes as needed.
- Last 15–20 minutes: Wind down carbohydrate intake and increase plain water if approaching the end of the session.
- Within 30 minutes after: Shift to protein and recovery nutrition; close the isotonic drink window.
Sample Stacks by Goal
Endurance (cycling, running >90 min):
- Isotonic drink with multiple carbohydrate types
- 1–2 energy gels during event (timed every 30–40 min)
- Additional electrolyte tablet if sweating heavily
Team sport or HIIT (60–75 min):
- Isotonic drink sipped throughout
- No gels needed for most sessions under 75 minutes
- Caffeine pre-workout if goal is performance
Recreational gym training (<60 min):
- Water or half-strength isotonic drink for sessions under 60 minutes at moderate intensity — full isotonic is unnecessary unless exercising in heat
What to Avoid
- Mixing isotonic drinks with stimulant-heavy pre-workouts at the same time — you lose control over total caffeine intake
- Using gels in the absence of water — always chase gels with water to maintain isotonicity in the gut
- Exceeding one isotonic drink serving without adjusting total daily fluid intake accordingly
FAQ
Can I use an isotonic drink and creatine together?
Yes. Take creatine in a small amount of water or juice separately — ideally around your workout window — rather than mixing it directly into the isotonic drink for a long session. The practical benefit of this separation is modest but avoids any minor stability issues.
Do I need an isotonic drink for a 30-minute workout?
For sessions under 45 minutes at moderate intensity, water alone is generally sufficient for most people exercising in a normal temperature environment. Isotonic drinks add meaningful value for longer, more intense sessions or hot conditions.
Are energy gels interchangeable with isotonic drinks?
They serve overlapping but distinct roles. Isotonic drinks replace fluid and electrolytes alongside carbohydrates. Gels deliver concentrated carbohydrates quickly but require separate water intake to maintain gut isotonicity. They work best used together during endurance events.
References
Doherty, M., & Smith, P. M. (2005). Effects of caffeine ingestion on exercise testing: a meta-analysis. International Journal of Sport Nutrition and Exercise Metabolism, 15(2), 130–149.
Jeukendrup, A. E. (2010). Carbohydrate and exercise performance: the role of multiple transportable carbohydrates. Current Opinion in Clinical Nutrition and Metabolic Care, 13(4), 452–457. https://pubmed.ncbi.nlm.nih.gov/20574242/
Crum, E. M., Lahart, I., Thompson, S. W., Stannard, S. R., & McKune, A. J. (2021). The effect of caffeine on endurance performance: a meta-analysis. Sports Medicine, 51(4), 661–692.
