Table of Contents
- Key Highlights
- Introduction
- How muscles recover: the biology behind the gains
- Glycogen replenishment: why speed matters and how to do it
- Amino acids and protein: stopping breakdown and triggering growth
- Tackling DOMS and inflammation with targeted nutrients
- Rehydration and electrolytes: restoring function at the cellular level
- Hormonal shift: suppressing cortisol and switching to growth mode
- Putting supplements into practice: science-backed post-workout protocols
- Whole foods vs supplements: when each makes sense
- Safety, quality and competition rules
- Common mistakes that blunt recovery
- Case studies: athletes and teams using targeted recovery
- Building a personalized recovery plan
- Practical shopping list and DIY recovery mixes
- FAQ
Key Highlights
- Targeted post-workout supplements speed glycogen restoration, supply essential amino acids for muscle repair, and restore electrolytes — enabling faster, more consistent training adaptations.
- A strategic post-exercise mix (fast carbs + high-quality protein + electrolytes) lowers cortisol, reduces delayed onset muscle soreness, and creates a cellular environment that favors muscle protein synthesis.
- Practical protocols — specific nutrient combinations, timing, and liquid versus whole-food choices — depend on training demands, recovery windows, and athlete goals; supplement quality and dosing matter for safety and effectiveness.
Introduction
Workouts tear muscle fibers. That stress drives adaptation, but the physical lifting happens in the gym while the biological rebuilding happens afterward. The speed and precision of nutrient delivery during the immediate recovery window determine whether damaged muscle fibers get patched up and strengthened, or whether progress stalls. For athletes and serious lifters, relying solely on whole meals often falls short because the body needs specific substrates delivered quickly to halt tissue breakdown, refill energy stores, and reset hormones that control growth.
Targeted recovery supplements are designed to do exactly that: restore glycogen, flood the bloodstream with essential amino acids, replace electrolytes lost in sweat, and shift the body out of a catabolic, high-cortisol state. The result is reduced soreness, less missed training, and improved long-term gains. The following sections unpack the physiology behind recovery, explain which nutrients make the biggest difference, and translate the science into practical, evidence-based protocols you can use after hard sessions.
How muscles recover: the biology behind the gains
Muscle adaptation is a two-step process: mechanical and metabolic damage during exercise, followed by molecular repair and remodeling. When you lift heavy or perform high-volume work, muscle fibers experience microscopic tears and cellular stress. That triggers a cascade of responses:
- Local inflammation recruits immune cells to clear debris and release growth factors.
- Satellite cells activate and fuse to damaged fibers, contributing to repair and hypertrophy.
- Muscle protein synthesis (MPS) increases, building new contractile proteins if the necessary amino acids and signaling molecules are present.
- Glycogen stores that powered the effort get depleted and need replenishing for future performance.
Nutrition interacts with each of these steps. Amino acids provide the raw material for MPS; carbohydrate availability dictates how quickly glycogen is restored; electrolytes and fluids restore cellular volume and nerve-muscle signalling; and certain nutrients blunt excessive oxidative stress and inflammation that can slow repair. The hormonal environment — insulin, cortisol, and growth factors — modulates whether the net effect after a workout is muscle gain or continued breakdown. Fast and precise nutrient delivery optimizes that environment for recovery.
Glycogen replenishment: why speed matters and how to do it
Glycogen is muscle carbohydrate stored as a dense energy reserve. Intense efforts, sprint intervals and long resistance sessions can reduce muscle glycogen substantially. When glycogen is low, training intensity suffers and the stimulus for adaptation weakens. Replenishing glycogen quickly matters most when athletes have limited recovery time between sessions — for example, twice-daily training, tournament play, or back-to-back workouts.
Why supplements? Fast-digesting carbohydrate sources — dextrose, maltodextrin, waxy maize starch, or specially-formulated recovery blends — raise blood glucose and trigger an insulin response. Insulin does two things: it drives glucose into muscle cells via GLUT4 translocation and it suppresses net protein breakdown. That combined effect accelerates glycogen repletion and preserves muscle tissue in the immediate hours after exercise.
Practical guidance
- When recovery time is constrained (less than 8 hours between sessions), prioritize rapid carbohydrates immediately after exercise. A practical post-session recovery drink often contains 20–60 grams of easily digestible carbs paired with protein.
- For single daily sessions where the next training is >24 hours away, rapid glycogen repletion is less urgent; whole-food meals across the day can be sufficient.
- Liquid carbohydrates absorb faster than solid food. That matters when the objective is to stimulate a quick insulin rise and shuttle nutrients into muscle.
Real-world example: endurance athletes often consume carbohydrate-electrolyte drinks or gels immediately after events to speed glycogen restoration between stages in multi-day races. Strength athletes who train twice a day or want to maximize repeated power output use dextrose-plus-whey shakes to restore muscle energy quickly.
Amino acids and protein: stopping breakdown and triggering growth
Proteins break down into amino acids. Among them, the branched-chain amino acid leucine plays a central role in triggering muscle protein synthesis by activating the mTOR pathway. Delivering a fast, high-quality source of essential amino acids (EAAs) to the blood after training provides both the signal and the substrate for rebuilding muscle.
Key points about post-workout protein:
- Dose matters. For most adults, 20–40 grams of high-quality protein (whey is particularly fast-absorbing) effectively stimulates maximal post-exercise MPS. That range ensures sufficient leucine (~2.5–3 g) and a broad profile of EAAs.
- Speed matters. Liquid or hydrolyzed protein forms appear in the bloodstream more rapidly than intact foods, delivering amino acids when the muscle is most primed for uptake.
- EAAs trump BCAAs alone. Consuming just BCAAs (leucine, isoleucine, valine) can stimulate MPS signaling, but without the other essential amino acids the body lacks the raw materials to synthesize new muscle tissue. Complete EAA mixes or intact high-quality protein are superior.
Mechanisms in practical terms
- Halting breakdown: Immediately after exercise, supplying amino acids reduces the need for the body to break down its own proteins for fuel or repair.
- Stimulating synthesis: Leucine activates mTOR, a molecular switch necessary for initiating new protein assembly.
- Repairing tissue: Amino acids are the actual building blocks used to stitch microscopic damage into stronger fibers.
Real-world example: collegiate and professional athletes typically consume 20–40 g whey-protein shakes within 30 minutes of training to maximize recovery while meeting daily protein needs.
Tackling DOMS and inflammation with targeted nutrients
Delayed onset muscle soreness (DOMS) peaks 24–72 hours after unaccustomed or intense exercise. DOMS is a symptom of acute inflammation and structural damage at the cellular level. Left unchecked, severe soreness reduces range of motion, diminishes training quality, and increases injury risk.
Nutritional interventions reduce the severity and duration of DOMS by addressing three targets: metabolic waste clearance, inflammation, and oxidative stress.
How supplements help
- Clearing metabolic byproducts: Rapid fluid and carbohydrate intake supports circulation and the removal of metabolic waste such as lactate and hydrogen ions that accompany intense work.
- Reducing inflammation: Specific nutrients — omega-3 fatty acids, vitamin D, and certain polyphenols — blunt excessive inflammatory signalling without completely blocking the acute inflammation necessary for adaptation.
- Neutralizing free radicals: Antioxidants (vitamin C, vitamin E, polyphenols such as those in tart cherry or blueberry) reduce oxidative damage that can exacerbate soreness. Timing matters: large antioxidant doses taken continuously may interfere with training adaptations; targeted use in the immediate recovery period or around competition is more strategic.
Evidence and considerations
- Tart cherry juice and concentrated anthocyanin blends have been shown in controlled trials to reduce post-exercise muscle pain and accelerate recovery of strength after eccentric or marathon-like events.
- Omega-3 supplementation (EPA/DHA) reduces markers of muscle damage and subjective soreness in several studies, particularly when doses are adequate and used over weeks.
- Avoid habitual, high-dose antioxidants immediately post-session if the training goal is to maximize long-term mitochondrial and oxidative adaptations; targeted, brief interventions can reduce acute soreness without necessarily blunting training responses.
Practical guidance
- For heavy eccentric sessions (slow lowers, downhill running) consider a brief regimen of tart cherry concentrate or anthocyanin-rich extracts in the 48 hours following the session.
- Include dietary sources of omega-3s and consider supplementation for athletes with chronically high inflammatory load.
- Use targeted antioxidant strategies when soreness threatens short-term performance or when rapid turnaround is required.
Rehydration and electrolytes: restoring function at the cellular level
Sweat is not just water; it contains sodium, potassium, chloride, magnesium and calcium — electrolytes that govern fluid balance, nerve conduction and muscle contraction. Replacing lost fluid alone can restore plasma volume, but without electrolytes cells remain dysfunctional and cramping, weakness or impaired performance follow.
How electrolytes restore recovery
- Sodium pulls water back into the circulation and into muscle cells, helping restore cell volume and nutrient transport.
- Potassium supports membrane potential, which is critical for muscle contraction and neural signalling.
- Magnesium and calcium are cofactors in enzymatic reactions and muscle contractility.
Advantages of formulated recovery drinks
- Balanced electrolyte blends accelerate rehydration more effectively than plain water by restoring osmotic gradients that permit water to move into cells.
- Including some carbohydrate in the drink increases fluid uptake via sodium-glucose cotransport mechanisms and supports glycogen synthesis.
Practical guidance
- For most workouts under 60 minutes with moderate sweat, water plus a balanced meal will suffice. For heavy sweating or sessions over an hour, choose a recovery drink that provides electrolytes along with carbohydrates and protein.
- Athletes with heavy sweat rates or salty sweaters should focus on replacing sodium; typical sports-recovery formulations include sodium to aid fluid retention and prevent hyponatremia in prolonged efforts.
- Rehydration is also linked to recovery because proper cellular hydration optimizes enzymatic processes involved in protein synthesis and glycogen restoration.
Real-world example: team-sport athletes on back-to-back days use electrolyte-protein-carbohydrate shakes to restore both fluid balance and energy while streamlining intake between training sessions and games.
Hormonal shift: suppressing cortisol and switching to growth mode
Cortisol is a catabolic hormone released during exercise to mobilize energy. Acute cortisol spikes are useful, but prolonged elevation after a workout impairs muscle repair by promoting protein breakdown. Insulin counters cortisol’s catabolic effect by driving nutrients into cells and inhibiting proteolysis.
How nutrition manipulates hormones
- Fast-absorbing carbohydrates generate an insulin spike that suppresses post-exercise cortisol and supports glycogen resynthesis.
- Adding protein amplifies the anti-catabolic effect by providing amino acids and stimulating insulin further.
- Certain amino acids and small peptides can modulate stress hormone responses and immune signalling.
Practical application
- When the goal is to shift rapidly to an anabolic state — for instance, in athletes training multiple times per day — consume a carbohydrate-plus-protein recovery drink immediately after the session. That combination reduces cortisol, increases insulin, and supplies substrates for repair.
- For single daily sessions with ample recovery time, timing is more flexible; however, taking advantage of the early post-exercise window yields measurable benefits in glycogen restoration and acute suppression of catabolic signalling.
Evidence note: the magnitude of insulin needed to drive muscle glycogen synthesis and inhibit proteolysis is moderate; pairing about 20–40 g of carbs with 15–30 g of protein is a practical approach that balances hormonal outcomes without excessive calories.
Putting supplements into practice: science-backed post-workout protocols
Translating mechanism into practice requires tailoring to training type, frequency, and athlete goals. Below are protocols informed by the science and used by coaches and sports nutritionists.
A. Strength-focused session (single daily workout, goal: hypertrophy)
- Immediate (0–60 minutes): 20–40 g whey protein or EAA blend; optional 10–20 g fast carbs if appetite is low.
- Next meal (1–3 hours): balanced whole-food meal with 30–40 g protein, moderate carbs and healthy fats.
- Rationale: complete amino acid availability to maximize MPS; glycogen repletion less urgent unless the session was unusually long.
B. Two-a-day or tournament play (short recovery window)
- Immediate (within 30 minutes): 20–40 g whey + 30–60 g fast carbs (dextrose/maltodextrin) + electrolyte mix.
- Between sessions: portable carbohydrate snacks (fruit, gels) and small protein servings; maintain hydration.
- Rationale: rapid glycogen restoration, insulin-mediated suppression of cortisol, and fluid/electrolyte replacement to maintain performance.
C. Endurance event or long-distance training
- During event: carbohydrate-electrolyte drink to maintain fuel.
- Immediate post-event: 0.5–0.7 g/kg carbohydrate plus 20–40 g protein in the first 30–60 minutes; continue to eat carbohydrate-rich meals over the next 4–24 hours.
- Rationale: maximize glycogen resynthesis and start repair quickly to prevent performance decline on subsequent days.
D. Eccentric or novel high-DOMS sessions
- Immediate: 20–40 g protein + moderate carb; include an antioxidant-rich concentrated tart cherry or polyphenol beverage as tolerated.
- Following 48 hours: continue anti-inflammatory nutritional strategies (omega-3s, polyphenols) and active recovery modalities (light movement, mobility).
- Rationale: reduce prolonged inflammation and accelerate functional recovery to preserve subsequent training quality.
Practical recipes
- Basic post-workout shake: 30 g whey isolate + 40 g dextrose + 300–500 ml water + pinch of salt. Blend and drink within 30 minutes.
- Whole-food alternative (if time allows): Greek yogurt (200 g) mixed with honey (1–2 tablespoons), banana, and a small handful of oats — delivers protein, carbs and electrolytes in palatable form.
Liquid forms digest faster; powders and hydrolyzed proteins are useful when speed is the priority. For athletes subject to testing, choose third-party-tested products to avoid banned substances.
Whole foods vs supplements: when each makes sense
Supplements are tools, not replacements. Whole foods provide broader nutrient profiles — micronutrients, fiber and phytonutrients — and should form the foundation of an athlete’s diet. Supplements provide speed, convenience and precision.
When to choose supplements
- Rapid recovery windows: multiple daily sessions, competitions with short turnarounds, when appetite is suppressed post-event.
- Controlled dosing: exact carbohydrate-to-protein ratios, known caloric load and quick absorption.
- Portability and consistency: travel, stadium locker rooms, or situations where preparing a balanced meal is impractical.
When whole foods are sufficient
- Single daily sessions with ample recovery time.
- Athletes who tolerate meals and prefer dietary variety.
- Situations emphasizing long-term health and micronutrient adequacy over immediate physiologic manipulation.
Hybrid approach
- Use a fast-acting supplement immediately after training, then follow with a nutrient-dense whole-food meal within 1–3 hours. This strategy takes advantage of rapid nutrient delivery while ensuring broad micronutrient intake.
Safety, quality and competition rules
Supplements are not tightly regulated in all jurisdictions. Contamination, inaccurate labeling and adulteration are real risks, particularly for athletes subject to anti-doping regulations. Safety considerations include:
- Third-party testing: Choose products certified by recognized organizations (Informed-Sport, NSF Certified for Sport, BSCG) to reduce the risk of banned substances.
- Protein and kidney health: High daily protein intakes are generally safe for healthy individuals. Caution is warranted for people with pre-existing kidney disease; consult a clinician.
- Sugar load: Frequent use of high-carbohydrate recovery formulas increases caloric intake. Athletes planning weight loss or those with metabolic concerns should tailor intake to training load.
- Drug interactions and underlying conditions: Some herbal extracts or high-dose vitamins may interact with medications or medical conditions. Review with a healthcare provider.
Label literacy
- Check ingredient lists for fillers, proprietary blends and unexpected stimulants.
- Verify macronutrient breakdown to match intended recovery goals.
- Prefer isolates or hydrolysates when rapid absorption is required.
Common mistakes that blunt recovery
- Skipping the early post-workout window when sessions are close together: delayed feeding increases glycogen restoration time and prolongs catabolic signalling.
- Relying on BCAAs alone: without the full complement of EAAs, protein synthesis lacks the necessary raw materials.
- Overdoing antioxidants: chronic high-dose antioxidants may impair some training adaptations; use them strategically.
- Ignoring electrolytes: consuming plain water after heavy sweating dilutes plasma sodium and may impair rehydration and recovery.
- Using low-quality supplements: contaminated or mislabeled products can lead to banned substance positives for competitive athletes and deliver inconsistent results.
Case studies: athletes and teams using targeted recovery
Professional sports teams and endurance squads routinely incorporate strategic recovery nutrition into daily practice. Examples illustrate how theory translates to outcomes.
- Cyclists during stage races: teams supply carbohydrate-electrolyte solutions and fast-protein concentrates immediately after each stage. Riders who prioritize immediate refueling maintain higher power output on subsequent stages and report reduced cumulative fatigue.
- Rugby squads with twice-daily training: post-session recovery beverages with 30–60 g carbohydrates and 20–30 g protein shorten recovery time, reduce soreness and preserve training intensity for the afternoon session.
- Marathon runners: a rapid post-race carb-protein intake combined with tart cherry concentrate in the days after a marathon speeds restoration of running economy and reduces soreness, enabling a quicker return to maintenance runs.
These protocols reflect the same physiological principles: immediate substrate provision, hormonal modulation, and fluid/electrolyte restoration produce measurable benefits in both subjective recovery and objective performance.
Building a personalized recovery plan
Design recovery nutrition around three variables: training load, recovery window, and individual physiology.
- Assess training load
- Short, intense sessions with long recovery allow flexible feeding.
- Repeated or prolonged sessions demand immediate, targeted intake.
- Define the recovery window
- If the next session occurs within 8 hours, prioritize rapid carbohydrate and protein intake immediately after exercise.
- For single daily sessions, distribute protein evenly across meals and include a post-workout protein source for convenience.
- Match the product to the goal
- Strength/hypertrophy: prioritize protein dose (20–40 g) with moderate carbs for hormone modulation.
- Endurance: prioritize carbohydrate for glycogen restoration; include protein to assist repair.
- Rapid turnaround: choose liquid supplements with electrolytes.
- Monitor and adjust
- Track soreness, performance metrics, and body composition. If recovery stalls, increase carbohydrate during the early hours post-exercise or add targeted anti-inflammatory nutrients when appropriate.
Sample week for a semi-professional athlete training six days a week
- Daily morning session: immediate shake (30 g whey + 40 g dextrose + electrolytes), breakfast 60–90 minutes later.
- Afternoon/pm session: repeat immediate shake post-session if <8 hours since the morning workout; otherwise whole-food meal suffices.
- Recovery modalities: tart cherry concentrate after long runs or heavy eccentric sessions; omega-3 supplementation daily; sleep hygiene prioritized.
Practical shopping list and DIY recovery mixes
Core ingredients to have on hand:
- Whey protein isolate or hydrolysate (fast absorption)
- Dextrose or maltodextrin (rapid carbohydrate)
- Electrolyte powder or a pinch of high-quality salt plus potassium citrate/powder if needed
- Tart cherry concentrate or polyphenol-rich juice for targeted use
- Omega-3 (EPA/DHA) supplement for chronic anti-inflammatory support
- Portable EAA powders for situations where solid protein is impractical
DIY recovery shake template
- 25–35 g whey protein
- 30–60 g fast carbohydrate (adjust for body size and recovery needs)
- 300–500 ml fluid
- Pinch of salt or electrolyte powder
- Optional: 1 tsp tart cherry concentrate (for high-DOMS sessions)
Adjust volumes and dosages to match bodyweight, caloric goals and training intensity.
FAQ
Q: How soon after a workout should I consume a recovery drink? A: Within 30–60 minutes is ideal when rapid replenishment is needed — especially if you have another session within the same day. For single daily workouts with no time pressure, consuming protein and carbs within a few hours still supports recovery, but immediate intake accelerates glycogen restoration and suppresses catabolic hormones.
Q: Is whey better than plant proteins post-workout? A: Whey is absorbed rapidly and contains a high leucine content, making it highly effective for stimulating muscle protein synthesis. High-quality plant proteins can be effective when dosed appropriately (often slightly higher amounts or complementary blends to ensure a complete EAA profile). For speed and convenience, whey remains the most studied and reliable option.
Q: Do BCAAs alone work for recovery? A: BCAAs stimulate signaling pathways, but without the full complement of essential amino acids the body lacks building blocks required for net protein synthesis. Complete EAA supplements or intact protein sources are superior.
Q: How much carbohydrate should I take after endurance training? A: Take enough carbohydrate to replenish glycogen and support the next session. When rapid restoration is necessary, include a concentrated source immediately after exercise and continue feeding carbohydrates over the next several hours. Exact amounts depend on body size and training length; aim for an adequate portion to restore energy without overshooting daily needs.
Q: Will antioxidant supplements blunt training adaptations? A: Chronic, high-dose antioxidant supplementation can blunt some cellular adaptations to training by interfering with redox signalling. Targeted, short-term use (e.g., around competition or when DOMS threatens performance) is less likely to impair adaptations and can reduce acute soreness.
Q: How important are electrolytes in my recovery drink? A: Electrolytes are essential after high sweat losses. They restore osmotic balance, improve water absorption, and support muscle and nerve function. For sessions with significant sweat or longer durations, include sodium and potassium in your post-workout beverage.
Q: What about creatine — does it belong in a recovery drink? A: Creatine supports high-intensity performance and aids recovery when taken consistently. Timing is flexible; daily supplementation provides muscle creatine saturation. Some athletes add creatine to post-workout shakes for convenience, but immediate timing is less critical than consistent daily intake.
Q: Are there risks to frequent high-calorie recovery shakes? A: Yes. If training load does not justify the calories, frequent high-calorie shakes can lead to unwanted weight gain. Match post-workout nutrition to energy expenditure and overall body composition goals.
Q: How can I ensure my supplements are safe for competition? A: Use products certified by third-party testing organizations that screen for banned substances. Check labels carefully and maintain documentation for any supplements you use.
Q: Can I recover effectively on whole foods? A: Yes. Whole foods can fully support recovery given sufficient timing and nutrient intake, particularly when there is ample recovery time. Supplements provide speed and convenience when rapid nutrient delivery is required.
Q: How long do the effects of a good post-workout supplement last? A: Immediate benefits — reduced cortisol, amino acid availability and faster glycogen uptake — occur within hours. The downstream effects, such as enhanced training capacity and greater long-term gains, accumulate over weeks and months when recovery is consistent.
Q: What should I do if I feel unusually sore despite following recovery protocols? A: Reassess training volume and intensity, sleep quality, and overall dietary intake. Consider targeted anti-inflammatory nutrients (tart cherry, omega-3s), reduce training load temporarily, incorporate active recovery and consult a sports medicine professional if pain persists or function is impaired.
Q: Do non-athletes or recreational lifters need supplements? A: Recreational lifters can benefit from targeted supplements if they train frequently, have tight recovery windows, or find whole foods impractical. For many who train sporadically and have flexible meal windows, whole-food recovery is often sufficient.
Q: How do I personalize dosing for body size? A: Scale carbohydrate and protein to body weight and training load. Heavier athletes require more absolute grams of carbohydrate and protein. Work with a sports dietitian to refine precise grams based on body composition and performance goals.
Q: Is there a universal post-workout formula? A: No. Effective recovery depends on the athlete’s sport, training frequency, goals, and physiology. The core principles remain consistent — supply carbs to restore glycogen, provide EAAs to support protein synthesis, restore fluids and electrolytes, and modulate inflammation — but exact dosages and forms vary.
Q: Can I use whole fruits or foods instead of dextrose/maltodextrin? A: Yes. Fruit and starchy foods provide carbohydrates and some micronutrients. Liquid, refined carbs absorb faster; choose whole foods when time allows or when the training demand does not require immediate glycogen restoration.
Q: Should I be concerned about sugar in recovery drinks? A: Context matters. Post-workout carbohydrates restore glycogen and support recovery; the sugar in a recovery drink serves that physiological need. Adjust total daily carbohydrate to meet training demands and body composition targets to avoid excess.
Q: How long before bed should I eat protein after a late-night workout? A: Consuming 20–40 g of slow-digesting protein (casein) before sleep can enhance overnight muscle protein synthesis and recovery. If a fast-absorbing protein is taken immediately post-session, following with a small casein-containing snack before bed can be beneficial for prolonged amino acid availability overnight.
Q: Are there differences in recovery needs between genders? A: Both sexes follow the same fundamental principles, but individual differences in hormonal milieu, body composition and energy needs require personalized approaches. Female athletes may need more attention to energy availability and micronutrients.
Q: What role does sleep play in recovery compared to nutrition? A: Sleep is a primary driver of recovery. Hormonal regulation, protein synthesis, and neural recovery occur during sleep. Nutrition optimizes substrate availability; sleep enables repair. Both are non-negotiable for consistent progress.
Targeted post-workout nutrition is not a quick fix; it’s a strategic component of training. When tailored to the demands of the session and the athlete’s schedule, the right mix of carbohydrates, high-quality protein, electrolytes and selective anti-inflammatory nutrients shortens recovery, reduces soreness and preserves the quality of subsequent sessions. Use supplements for precision and speed when needed, keep whole foods as the foundation, and prioritize quality, dosing and timing to convert every session into measurable progress.